1
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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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Takaya K, Okabe K, Sakai S, Aramaki-Hattori N, Asou T, Kishi K. Salicylate induces epithelial actin reorganization via activation of the AMP-activated protein kinase and promotes wound healing and contraction in mice. Sci Rep 2024; 14:16442. [PMID: 39013997 PMCID: PMC11252334 DOI: 10.1038/s41598-024-67266-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 07/09/2024] [Indexed: 07/18/2024] Open
Abstract
Wounds that occur in adults form scars due to fibrosis, whereas those in embryos regenerate. If wound healing in embryos is mimicked in adults, scarring can be reduced. We found that mouse fetuses could regenerate tissues up to embryonic day (E) 13, but visible scars remained thereafter. This regeneration pattern requires actin cable formation at the epithelial wound margin via activation of adenosine monophosphate (AMP)-activated protein kinase (AMPK). Here, we investigated whether the AMPK-activating effect of salicylate, an anti-inflammatory drug, promotes regenerative wound healing. Salicylate administration resulted in actin cable formation and complete wound regeneration in E14 fetuses, in which scarring should have normally occurred, and promoted contraction of the panniculus carnosus muscle, resulting in complete wound regeneration. In vitro, salicylate further induced actin remodeling in mouse epidermal keratinocytes in a manner dependent on cell and substrate target-specific AMPK activation and subsequent regulation of Rac1 signaling. Furthermore, salicylate promoted epithelialization, enhanced panniculus carnosus muscle contraction, and inhibited scar formation in adult mice. Administration of salicylates to wounds immediately after injury may be a novel method for preventing scarring by promoting a wound healing pattern similar to that of embryonic wounds.
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Affiliation(s)
- Kento Takaya
- Department of Plastic and Reconstructive Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-Ku, Tokyo, 160-8582, Japan
| | - Keisuke Okabe
- Department of Plastic and Reconstructive Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-Ku, Tokyo, 160-8582, Japan
| | - Shigeki Sakai
- Department of Plastic and Reconstructive Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-Ku, Tokyo, 160-8582, Japan
| | - Noriko Aramaki-Hattori
- Department of Plastic and Reconstructive Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-Ku, Tokyo, 160-8582, Japan
| | - Toru Asou
- Department of Plastic and Reconstructive Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-Ku, Tokyo, 160-8582, Japan
| | - Kazuo Kishi
- Department of Plastic and Reconstructive Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-Ku, Tokyo, 160-8582, Japan.
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3
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Rezvan A, Romain G, Fathi M, Heeke D, Martinez-Paniagua M, An X, Bandey IN, Montalvo MJ, Adolacion JRT, Saeedi A, Sadeghi F, Fousek K, Puebla-Osorio N, Cooper LJN, Bernatchez C, Singh H, Ahmed N, Mattie M, Bot A, Neelapu S, Varadarajan N. Identification of a clinically efficacious CAR T cell subset in diffuse large B cell lymphoma by dynamic multidimensional single-cell profiling. NATURE CANCER 2024; 5:1010-1023. [PMID: 38750245 DOI: 10.1038/s43018-024-00768-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 04/10/2024] [Indexed: 05/24/2024]
Abstract
Chimeric antigen receptor (CAR) T cells used for the treatment of B cell malignancies can identify T cell subsets with superior clinical activity. Here, using infusion products of individuals with large B cell lymphoma, we integrated functional profiling using timelapse imaging microscopy in nanowell grids with subcellular profiling and single-cell RNA sequencing to identify a signature of multifunctional CD8+ T cells (CD8-fit T cells). CD8-fit T cells are capable of migration and serial killing and harbor balanced mitochondrial and lysosomal volumes. Using independent datasets, we validate that CD8-fit T cells (1) are present premanufacture and are associated with clinical responses in individuals treated with axicabtagene ciloleucel, (2) longitudinally persist in individuals after treatment with CAR T cells and (3) are tumor migrating cytolytic cells capable of intratumoral expansion in solid tumors. Our results demonstrate the power of multimodal integration of single-cell functional assessments for the discovery and application of CD8-fit T cells as a T cell subset with optimal fitness in cell therapy.
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Affiliation(s)
- Ali Rezvan
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, USA
| | - Gabrielle Romain
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, USA
| | | | | | | | - Xingyue An
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, USA
| | - Irfan N Bandey
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, USA
| | - Melisa J Montalvo
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, USA
| | - Jay R T Adolacion
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, USA
| | - Arash Saeedi
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, USA
| | - Fatemeh Sadeghi
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, USA
| | - Kristen Fousek
- Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA
| | - Nahum Puebla-Osorio
- Department of Lymphoma and Myeloma, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Chantale Bernatchez
- Department of Biologics Development, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Harjeet Singh
- Divsion of Pediatrics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Nabil Ahmed
- Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA
| | - Mike Mattie
- Kite, a Gilead Company, Santa Monica, CA, USA
| | - Adrian Bot
- Kite, a Gilead Company, Santa Monica, CA, USA
| | - Sattva Neelapu
- Department of Lymphoma and Myeloma, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Navin Varadarajan
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, USA.
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4
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Colmer SF, Adams AA, Adam E, Miller R, Stefanovski D, Kulp JC, van Eps A. The effect of pre-dosing with metformin on the insulin response to oral sugar in insulin-dysregulated horses. Equine Vet J 2024; 56:318-325. [PMID: 37545128 DOI: 10.1111/evj.13979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 07/13/2023] [Indexed: 08/08/2023]
Abstract
BACKGROUND A single dose of metformin administered 1 h prior to oral glucose challenge was previously shown to reduce insulinaemic responses in horses with experimentally-induced insulin dysregulation (ID). Targeted administration could be useful for controlling post-prandial hyperinsulinaemia in horses with naturally-occurring ID. OBJECTIVES The objective was to compare the insulinaemic and glycaemic responses to oral sugar testing (OST) performed at different intervals after a single dose of metformin in horses with naturally-occurring ID. We hypothesised that pre-treatment with one dose of metformin would significantly decrease the insulinaemic response to OST. STUDY DESIGN Randomised cross-over in vivo experiment. METHODS Eight university-owned adult horses with naturally-occurring ID underwent OST 1, 2 and 6 h following a single oral dose of metformin (30 mg/kg) or 1 h after placebo (240 mL water) with a 7-day washout between treatments over a period of 3 weeks. Plasma insulin, C-peptide and glucose concentrations were measured at 0, 60 and 90 min after 0.45 mL/kg light corn syrup and the effect of treatment (and the interval since dosing) examined using a mixed effects linear regression model. RESULTS Metformin treatment had no significant effect on plasma glucose, insulin or C-peptide concentrations at any time point compared with placebo (p > 0.05). For OST 1 h post metformin, median (IQR) plasma insulin was 91.3 (62.4-114.9) μIU/mL at 60 min versus 76.2 (59.1-134.5) for placebo (p = 0.8) and 62.7 (31.4-109.7) at 90 min versus 51.8 (29.2-126.3) for placebo (p = 0.9). MAIN LIMITATIONS Small sample size may limit identification of more subtle decreases in insulin concentration with metformin pre-dosing. The results of this study are relevant only for one pre-treatment dose (30 mg/kg) which limits extrapolation to predictions about the effects of longer-term metformin administration on insulin and glucose dynamics in the horse. CONCLUSIONS AND CLINICAL IMPORTANCE The results do not support the use of targeted metformin treatment to reduce post-prandial hyperinsulinaemia in horses with naturally-occurring ID.
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Affiliation(s)
- Sarah F Colmer
- Department of Clinical Studies-New Bolton Center, The University of Pennsylvania School of Veterinary Medicine, Kennett Square, Pennsylvania, USA
| | - Amanda A Adams
- Department of Veterinary Science, Gluck Equine Research Center, The University of Kentucky College of Agriculture, Food and Environment, Lexington, Kentucky, USA
| | - Emma Adam
- Department of Veterinary Science, Gluck Equine Research Center, The University of Kentucky College of Agriculture, Food and Environment, Lexington, Kentucky, USA
| | - Rachel Miller
- Department of Clinical Sciences, Lincoln Memorial University College of Veterinary Medicine, Harrogate, Tennessee, USA
| | - Darko Stefanovski
- Department of Clinical Studies-New Bolton Center, The University of Pennsylvania School of Veterinary Medicine, Kennett Square, Pennsylvania, USA
| | - Jeaneen C Kulp
- Department of Clinical Studies-New Bolton Center, The University of Pennsylvania School of Veterinary Medicine, Kennett Square, Pennsylvania, USA
| | - Andrew van Eps
- Department of Clinical Studies-New Bolton Center, The University of Pennsylvania School of Veterinary Medicine, Kennett Square, Pennsylvania, USA
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5
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Takaya K, Okabe K, Sakai S, Aramaki-Hattori N, Asou T, Kishi K. Compound 13 Promotes Epidermal Healing in Mouse Fetuses via Activation of AMPK. Biomedicines 2023; 11:biomedicines11041013. [PMID: 37189631 DOI: 10.3390/biomedicines11041013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 03/15/2023] [Accepted: 03/20/2023] [Indexed: 03/29/2023] Open
Abstract
Unlike adults, early developing fetuses can completely regenerate tissue, and replicating this could lead to the development of treatments to reduce scarring. Mice epidermal structures, including wound healing patterns, are regenerated until embryonic day (E) 13, leaving visible scars thereafter. These patterns require actin cable formation at the epithelial wound margin through AMP-activated protein kinase (AMPK) activation. We aimed to investigate whether the administration of compound 13 (C13), a recently discovered AMPK activator, to the wound could reproduce this actin remodeling and skin regeneration pattern through its AMPK activating effect. The C13 administration resulted in partial formations of actin cables, which would normally result in scarring, and scar reduction during the healing of full-layer skin defects that occurred in E14 and E15 fetuses. Furthermore, C13 was found to cause AMPK activation in these embryonic mouse epidermal cells. Along with AMPK activation, Rac1 signaling, which is involved in leaflet pseudopodia formation and cell migration, was suppressed in C13-treated wounds, indicating that C13 inhibits epidermal cell migration. This suggests that actin may be mobilized by C13 for cable formation. Administration of C13 to wounds may achieve wound healing similar to regenerative wound healing patterns and may be a potential candidate for new treatments to heal scars.
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6
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Jamsheer K M, Kumar M, Srivastava V. SNF1-related protein kinase 1: the many-faced signaling hub regulating developmental plasticity in plants. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:6042-6065. [PMID: 33693699 DOI: 10.1093/jxb/erab079] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 02/17/2021] [Indexed: 05/03/2023]
Abstract
The Snf1-related protein kinase 1 (SnRK1) is the plant homolog of the heterotrimeric AMP-activated protein kinase/sucrose non-fermenting 1 (AMPK/Snf1), which works as a major regulator of growth under nutrient-limiting conditions in eukaryotes. Along with its conserved role as a master regulator of sugar starvation responses, SnRK1 is involved in controlling the developmental plasticity and resilience under diverse environmental conditions in plants. In this review, through mining and analyzing the interactome and phosphoproteome data of SnRK1, we are highlighting its role in fundamental cellular processes such as gene regulation, protein synthesis, primary metabolism, protein trafficking, nutrient homeostasis, and autophagy. Along with the well-characterized molecular interaction in SnRK1 signaling, our analysis highlights several unchartered regions of SnRK1 signaling in plants such as its possible communication with chromatin remodelers, histone modifiers, and inositol phosphate signaling. We also discuss potential reciprocal interactions of SnRK1 signaling with other signaling pathways and cellular processes, which could be involved in maintaining flexibility and homeostasis under different environmental conditions. Overall, this review provides a comprehensive overview of the SnRK1 signaling network in plants and suggests many novel directions for future research.
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Affiliation(s)
- Muhammed Jamsheer K
- Amity Food & Agriculture Foundation, Amity University Uttar Pradesh, Sector 125, Noida 201313, India
| | - Manoj Kumar
- Amity Food & Agriculture Foundation, Amity University Uttar Pradesh, Sector 125, Noida 201313, India
| | - Vibha Srivastava
- Department of Crop, Soil & Environmental Sciences, University of Arkansas, Fayetteville, AR, USA
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7
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Canagliflozin protects against sepsis capillary leak syndrome by activating endothelial α1AMPK. Sci Rep 2021; 11:13700. [PMID: 34211080 PMCID: PMC8249425 DOI: 10.1038/s41598-021-93156-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 06/16/2021] [Indexed: 02/08/2023] Open
Abstract
Sepsis capillary leak syndrome (SCLS) is an independent prognostic factor for poor sepsis outcome. We previously demonstrated that α1AMP-activated protein kinase (α1AMPK) prevents sepsis-induced vascular hyperpermeability by mechanisms involving VE-cadherin (VE-Cad) stabilization and activation of p38 mitogen activated protein kinase/heat shock protein of 27 kDa (p38MAPK/HSP27) pathway. Canagliflozin, a sodium-glucose co-transporter 2 inhibitor, has recently been proven to activate AMPK in endothelial cells. Therefore, we hypothesized that canagliflozin could be of therapeutic potential in patients suffering from SCLS. We herein report that canagliflozin, used at clinically relevant concentrations, counteracts lipopolysaccharide-induced vascular hyperpermeability and albumin leakage in wild-type, but not in endothelial-specific α1AMPK-knockout mice. In vitro, canagliflozin was demonstrated to activate α1AMPK/p38MAPK/HSP27 pathway and to preserve VE-Cad’s integrity in human endothelial cells exposed to human septic plasma. In conclusion, our data demonstrate that canagliflozin protects against SCLS via an α1AMPK-dependent pathway, and lead us to consider novel therapeutic perspectives for this drug in SCLS.
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8
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Acheva A, Kärki T, Schaible N, Krishnan R, Tojkander S. Adipokine Leptin Co-operates With Mechanosensitive Ca 2 +-Channels and Triggers Actomyosin-Mediated Motility of Breast Epithelial Cells. Front Cell Dev Biol 2021; 8:607038. [PMID: 33490070 PMCID: PMC7815691 DOI: 10.3389/fcell.2020.607038] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 12/07/2020] [Indexed: 12/24/2022] Open
Abstract
In postmenopausal women, a major risk factor for the development of breast cancer is obesity. In particular, the adipose tissue-derived adipokine leptin has been strongly linked to tumor cell proliferation, migration, and metastasis, but the underlying mechanisms remain unclear. Here we show that treatment of normal mammary epithelial cells with leptin induces EMT-like features characterized by higher cellular migration speeds, loss of structural ordering of 3D-mammo spheres, and enhancement of epithelial traction forces. Mechanistically, leptin triggers the phosphorylation of myosin light chain kinase-2 (MLC-2) through the interdependent activity of leptin receptor and Ca2+ channels. These data provide evidence that leptin-activated leptin receptors, in co-operation with mechanosensitive Ca2+ channels, play a role in the development of breast carcinomas through the regulation of actomyosin dynamics.
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Affiliation(s)
- Anna Acheva
- Section of Pathology, Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | - Tytti Kärki
- Department of Applied Physics, School of Science, Aalto University, Espoo, Finland
| | - Niccole Schaible
- Beth Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Ramaswamy Krishnan
- Beth Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Sari Tojkander
- Section of Pathology, Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
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9
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Daum R, Mrsic I, Hutterer J, Junginger A, Hinderer S, Meixner AJ, Gauglitz G, Chassé T, Schenke-Layland K. Fibronectin adsorption on oxygen plasma-treated polyurethane surfaces modulates endothelial cell response. J Mater Chem B 2021; 9:1647-1660. [DOI: 10.1039/d0tb02757j] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Fibronectin coating increases implant biocompatibility by enhancing surface endothelialization via integrin-mediated binding.
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Affiliation(s)
- Ruben Daum
- NMI Natural and Medical Sciences
- Institute at the University of Tübingen
- 72770 Reutlingen
- Germany
- Department of Women's Health
| | - Ivana Mrsic
- Institute of Physical and Theoretical Chemistry
- Eberhard Karls University Tübingen
- 72076 Tübingen
- Germany
| | - Johanna Hutterer
- Institute of Physical and Theoretical Chemistry
- Eberhard Karls University Tübingen
- 72076 Tübingen
- Germany
| | - Achim Junginger
- Institute of Physical and Theoretical Chemistry
- Eberhard Karls University Tübingen
- 72076 Tübingen
- Germany
| | - Svenja Hinderer
- NMI Natural and Medical Sciences
- Institute at the University of Tübingen
- 72770 Reutlingen
- Germany
- Department of Women's Health
| | - Alfred J. Meixner
- Institute of Physical and Theoretical Chemistry
- Eberhard Karls University Tübingen
- 72076 Tübingen
- Germany
- Center for Light–Matter Interaction
| | - Günter Gauglitz
- Institute of Physical and Theoretical Chemistry
- Eberhard Karls University Tübingen
- 72076 Tübingen
- Germany
| | - Thomas Chassé
- Institute of Physical and Theoretical Chemistry
- Eberhard Karls University Tübingen
- 72076 Tübingen
- Germany
- Center for Light–Matter Interaction
| | - Katja Schenke-Layland
- NMI Natural and Medical Sciences
- Institute at the University of Tübingen
- 72770 Reutlingen
- Germany
- Department of Women's Health
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10
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Jansens RJJ, Marmiroli S, Favoreel HW. An Unbiased Approach to Mapping the Signaling Network of the Pseudorabies Virus US3 Protein. Pathogens 2020; 9:pathogens9110916. [PMID: 33167340 PMCID: PMC7694389 DOI: 10.3390/pathogens9110916] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 11/01/2020] [Accepted: 11/03/2020] [Indexed: 01/18/2023] Open
Abstract
The US3 serine/threonine protein kinase is conserved among the alphaherpesvirus family and represents an important virulence factor. US3 plays a role in viral nuclear egress, induces dramatic alterations of the cytoskeleton, represses apoptosis, enhances gene expression and modulates the immune response. Although several substrates of US3 have been identified, an unbiased screen to identify US3 phosphorylation targets has not yet been described. Here, we perform a shotgun and phosphoproteomics analysis of cells expressing the US3 protein of pseudorabies virus (PRV) to identify US3 phosphorylation targets in an unbiased way. We identified several cellular proteins that are differentially phosphorylated upon US3 expression and validated the phosphorylation of lamin A/C at serine 404, both in US3-transfected and PRV-infected cells. These results provide new insights into the signaling network of the US3 protein kinase and may serve as a basis for future research into the role of the US3 protein in the viral replication cycle.
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Affiliation(s)
- Robert J. J. Jansens
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium;
| | - Sandra Marmiroli
- Cellular Signaling Laboratory, Department of Surgery, Medicine, Dentistry, and Morphology, University of Modena & Reggio Emilia, 41121 Modena, Italy;
| | - Herman W. Favoreel
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium;
- Correspondence:
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11
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Kulkarni PP, Sonkar VK, Gautam D, Dash D. AMPK inhibition protects against arterial thrombosis while sparing hemostasis through differential modulation of platelet responses. Thromb Res 2020; 196:175-185. [PMID: 32890901 DOI: 10.1016/j.thromres.2020.08.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 07/29/2020] [Accepted: 08/21/2020] [Indexed: 11/26/2022]
Abstract
AMP-activated protein kinase (AMPK) is a metabolic master switch that has critical role in wide range of pathologies including cardiovascular disorders. As AMPK-α2 knockout mice exhibit impaired thrombus stability, we asked whether pharmacological inhibition of AMPK with a specific small-molecule inhibitor, compound C, could protect against arterial thrombosis without affecting hemostasis. Mice pre-administered with compound C exhibited decreased mesenteric arteriolar thrombosis but normal tail bleeding time compared to vehicle-treated animals. Compound C potently restricted platelet aggregation, clot retraction and integrin activation induced by thrombin and collagen. It impaired platelet spreading on both immobilized fibrinogen and collagen matrices; it, however, had no significant effect on thrombin-induced phosphatidylserine exposure that is characteristic of procoagulant platelets. In parallel, compound C brought about significant drop in thrombin-induced phosphorylation of myosin light chain (MLC) and MLC phosphatase (MYPT1) as well as abrogated rise in level of RhoA-GTP in thrombin-stimulated platelets. Thus, effects of compound C on agonist-induced platelet responses could be at least in part attributed to modulation of cytoskeletal changes mediated by RhoA-MYPT1-MLC signaling. An ideal antithrombotic drug would spare hemostatic responses that maintain vascular integrity while preferentially protecting against thrombosis. The present study suggests that AMPK could be one such potential therapeutic target.
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Affiliation(s)
- Paresh P Kulkarni
- Centre for Advanced Research on Platelet Signaling and Thrombosis Biology (ICMR), Department of Biochemistry, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Vijay K Sonkar
- Centre for Advanced Research on Platelet Signaling and Thrombosis Biology (ICMR), Department of Biochemistry, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India; Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Deepa Gautam
- Centre for Advanced Research on Platelet Signaling and Thrombosis Biology (ICMR), Department of Biochemistry, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Debabrata Dash
- Centre for Advanced Research on Platelet Signaling and Thrombosis Biology (ICMR), Department of Biochemistry, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India.
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12
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Angé M, Castanares-Zapatero D, De Poortere J, Dufeys C, Courtoy GE, Bouzin C, Quarck R, Bertrand L, Beauloye C, Horman S. α1AMP-Activated Protein Kinase Protects against Lipopolysaccharide-Induced Endothelial Barrier Disruption via Junctional Reinforcement and Activation of the p38 MAPK/HSP27 Pathway. Int J Mol Sci 2020; 21:ijms21155581. [PMID: 32759774 PMCID: PMC7432762 DOI: 10.3390/ijms21155581] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/28/2020] [Accepted: 07/30/2020] [Indexed: 12/11/2022] Open
Abstract
Vascular hyperpermeability is a determinant factor in the pathophysiology of sepsis. While, AMP-activated protein kinase (AMPK) is known to play a role in maintaining endothelial barrier function in this condition. Therefore, we investigated the underlying molecular mechanisms of this protective effect. α1AMPK expression and/or activity was modulated in human dermal microvascular endothelial cells using either α1AMPK-targeting small interfering RNA or the direct pharmacological AMPK activator 991, prior to lipopolysaccharide (LPS) treatment. Western blotting was used to analyze the expression and/or phosphorylation of proteins that compose cellular junctions (zonula occludens-1 (ZO-1), vascular endothelial cadherin (VE-Cad), connexin 43 (Cx43)) or that regulate actin cytoskeleton (p38 MAPK; heat shock protein 27 (HSP27)). Functional endothelial permeability was assessed by in vitro Transwell assays, and quantification of cellular junctions in the plasma membrane was assessed by immunofluorescence. Actin cytoskeleton remodeling was evaluated through actin fluorescent staining. We consequently demonstrate that α1AMPK deficiency is associated with reduced expression of CX43, ZO-1, and VE-Cad, and that the drastic loss of CX43 is likely responsible for the subsequent decreased expression and localization of ZO-1 and VE-Cad in the plasma membrane. Moreover, α1AMPK activation by 991 protects against LPS-induced endothelial barrier disruption by reinforcing cortical actin cytoskeleton. This is due to a mechanism that involves the phosphorylation of p38 MAPK and HSP27, which is nonetheless independent of the small GTPase Rac1. This results in a drastic decrease of LPS-induced hyperpermeability. We conclude that α1AMPK activators that are suitable for clinical use may provide a specific therapeutic intervention that limits sepsis-induced vascular leakage.
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Affiliation(s)
- Marine Angé
- Pôle de Recherche Cardiovasculaire (CARD), Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium; (M.A.); (D.C.-Z.); (J.D.P.); (C.D.); (L.B.); (C.B.)
| | - Diego Castanares-Zapatero
- Pôle de Recherche Cardiovasculaire (CARD), Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium; (M.A.); (D.C.-Z.); (J.D.P.); (C.D.); (L.B.); (C.B.)
- Division of Intensive Care, Cliniques Universitaires Saint Luc, 1200 Brussels, Belgium
| | - Julien De Poortere
- Pôle de Recherche Cardiovasculaire (CARD), Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium; (M.A.); (D.C.-Z.); (J.D.P.); (C.D.); (L.B.); (C.B.)
| | - Cécile Dufeys
- Pôle de Recherche Cardiovasculaire (CARD), Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium; (M.A.); (D.C.-Z.); (J.D.P.); (C.D.); (L.B.); (C.B.)
| | - Guillaume E. Courtoy
- IREC Imaging Platform, Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium; (G.E.C.); (C.B.)
| | - Caroline Bouzin
- IREC Imaging Platform, Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium; (G.E.C.); (C.B.)
| | - Rozenn Quarck
- Department of Chronic Diseases & Metabolism (CHROMETA), Laboratory of Respiratory Diseases & Thoracic Surgery (BREATHE), KU Leuven, 3000 Leuven, Belgium;
| | - Luc Bertrand
- Pôle de Recherche Cardiovasculaire (CARD), Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium; (M.A.); (D.C.-Z.); (J.D.P.); (C.D.); (L.B.); (C.B.)
| | - Christophe Beauloye
- Pôle de Recherche Cardiovasculaire (CARD), Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium; (M.A.); (D.C.-Z.); (J.D.P.); (C.D.); (L.B.); (C.B.)
- Division of Cardiology, Cliniques Universitaires Saint-Luc, 1200 Brussels, Belgium
| | - Sandrine Horman
- Pôle de Recherche Cardiovasculaire (CARD), Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium; (M.A.); (D.C.-Z.); (J.D.P.); (C.D.); (L.B.); (C.B.)
- Correspondence: ; Tel.: +32-2-764-55-66
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13
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The influence of hypoxia and energy depletion on the response of endothelial cells to the vascular disrupting agent combretastatin A-4-phosphate. Sci Rep 2020; 10:9926. [PMID: 32555222 PMCID: PMC7303175 DOI: 10.1038/s41598-020-66568-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 05/15/2020] [Indexed: 12/25/2022] Open
Abstract
Combretastatin A-4 phosphate (CA4P) is a microtubule-disrupting tumour-selective vascular disrupting agent (VDA). CA4P activates the actin-regulating RhoA-GTPase/ ROCK pathway, which is required for full vascular disruption. While hypoxia renders tumours resistant to many conventional therapies, little is known about its influence on VDA activity. Here, we found that active RhoA and ROCK effector phospho-myosin light chain (pMLC) were downregulated in endothelial cells by severe hypoxia. CA4P failed to activate RhoA/ROCK/pMLC but its activity was restored upon reoxygenation. Hypoxia also inhibited CA4P-mediated actinomyosin contractility, VE-cadherin junction disruption and permeability rise. Glucose withdrawal downregulated pMLC, and coupled with hypoxia, reduced pMLC faster and more profoundly than hypoxia alone. Concurrent inhibition of glycolysis (2-deoxy-D-glucose, 2DG) and mitochondrial respiration (rotenone) caused profound actin filament loss, blocked RhoA/ROCK signalling and rendered microtubules CA4P-resistant. Withdrawal of the metabolism inhibitors restored the cytoskeleton and CA4P activity. The AMP-activated kinase AMPK was investigated as a potential mediator of pMLC downregulation. Pharmacological AMPK activators that generate AMP, unlike allosteric activators, downregulated pMLC but only when combined with 2DG and/or rotenone. Altogether, our results suggest that Rho/ROCK and actinomyosin contractility are regulated by AMP/ATP levels independently of AMPK, and point to hypoxia/energy depletion as potential modifiers of CA4P response.
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14
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Dai Y, Amenov A, Ignatyeva N, Koschinski A, Xu H, Soong PL, Tiburcy M, Linke WA, Zaccolo M, Hasenfuss G, Zimmermann WH, Ebert A. Troponin destabilization impairs sarcomere-cytoskeleton interactions in iPSC-derived cardiomyocytes from dilated cardiomyopathy patients. Sci Rep 2020; 10:209. [PMID: 31937807 PMCID: PMC6959358 DOI: 10.1038/s41598-019-56597-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 09/13/2019] [Indexed: 12/14/2022] Open
Abstract
The sarcomeric troponin-tropomyosin complex is a critical mediator of excitation-contraction coupling, sarcomeric stability and force generation. We previously reported that induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) from patients with a dilated cardiomyopathy (DCM) mutation, troponin T (TnT)-R173W, display sarcomere protein misalignment and impaired contractility. Yet it is not known how TnT mutation causes dysfunction of sarcomere microdomains and how these events contribute to misalignment of sarcomeric proteins in presence of DCM TnT-R173W. Using a human iPSC-CM model combined with CRISPR/Cas9-engineered isogenic controls, we uncovered that TnT-R173W destabilizes molecular interactions of troponin with tropomyosin, and limits binding of PKA to local sarcomere microdomains. This attenuates troponin phosphorylation and dysregulates local sarcomeric microdomains in DCM iPSC-CMs. Disrupted microdomain signaling impairs MYH7-mediated, AMPK-dependent sarcomere-cytoskeleton filament interactions and plasma membrane attachment. Small molecule-based activation of AMPK can restore TnT microdomain interactions, and partially recovers sarcomere protein misalignment as well as impaired contractility in DCM TnT-R173W iPSC-CMs. Our findings suggest a novel therapeutic direction targeting sarcomere- cytoskeleton interactions to induce sarcomere re-organization and contractile recovery in DCM.
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Affiliation(s)
- Yuanyuan Dai
- Heart Center, Department of Cardiology and Pneumology, Goettingen, Germany.,DZHK (German Center for Cardiovascular Research), partner site, Goettingen, Germany
| | - Asset Amenov
- Heart Center, Department of Cardiology and Pneumology, Goettingen, Germany.,DZHK (German Center for Cardiovascular Research), partner site, Goettingen, Germany
| | - Nadezda Ignatyeva
- Heart Center, Department of Cardiology and Pneumology, Goettingen, Germany.,DZHK (German Center for Cardiovascular Research), partner site, Goettingen, Germany
| | - Andreas Koschinski
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, OX1 3PT, UK
| | - Hang Xu
- Heart Center, Department of Cardiology and Pneumology, Goettingen, Germany.,DZHK (German Center for Cardiovascular Research), partner site, Goettingen, Germany
| | - Poh Loong Soong
- Institute of Pharmacology, University of Goettingen, Robert-Koch-Str. 40, 37075, Goettingen, Germany.,DZHK (German Center for Cardiovascular Research), partner site, Goettingen, Germany
| | - Malte Tiburcy
- Institute of Pharmacology, University of Goettingen, Robert-Koch-Str. 40, 37075, Goettingen, Germany.,DZHK (German Center for Cardiovascular Research), partner site, Goettingen, Germany
| | - Wolfgang A Linke
- Heart Center, Department of Cardiology and Pneumology, Goettingen, Germany.,DZHK (German Center for Cardiovascular Research), partner site, Goettingen, Germany.,Institute of Physiology II, University of Muenster, Muenster, Germany
| | - Manuela Zaccolo
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, OX1 3PT, UK
| | - Gerd Hasenfuss
- Heart Center, Department of Cardiology and Pneumology, Goettingen, Germany.,DZHK (German Center for Cardiovascular Research), partner site, Goettingen, Germany
| | - Wolfram-Hubertus Zimmermann
- Institute of Pharmacology, University of Goettingen, Robert-Koch-Str. 40, 37075, Goettingen, Germany.,DZHK (German Center for Cardiovascular Research), partner site, Goettingen, Germany
| | - Antje Ebert
- Heart Center, Department of Cardiology and Pneumology, Goettingen, Germany. .,DZHK (German Center for Cardiovascular Research), partner site, Goettingen, Germany.
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15
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Wu J, Rowart P, Jouret F, Gassaway BM, Rajendran V, Rinehart J, Caplan MJ. Mechanisms involved in AMPK-mediated deposition of tight junction components to the plasma membrane. Am J Physiol Cell Physiol 2020; 318:C486-C501. [PMID: 31913699 DOI: 10.1152/ajpcell.00422.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
AMP-activated protein kinase (AMPK) activation promotes early stages of epithelial junction assembly. AMPK activation in MDCK renal epithelial cells facilitates localization of the junction-associated proteins aPKCζ and Par3 to the plasma membrane and promotes conversion of Cdc42, a key regulator of epithelial polarization and junction assembly, to its active GTP bound state. Furthermore, Par3 is an important regulator of AMPK-mediated aPKCζ localization. Both aPKCζ and Par3 serve as intermediates in AMPK-mediated junction assembly, with inhibition of aPKCζ activity or Par3 knockdown disrupting AMPK's ability to facilitate zonula occludens (ZO-1) localization. AMPK phosphorylates the adherens junction protein afadin and regulates its interaction with the tight-junction protein zonula occludens-1. Afadin is phosphorylated at two critical sites, S228 (residing within an aPKCζ consensus site) and S1102 (residing within an AMPK consensus site), that are differentially regulated during junction assembly and that exert different effects on the process. Expression of phospho-defective mutants (S228A and S1102A) perturbed ZO-1 localization to the plasma membrane during AMPK-induced junction assembly. Expression of S228A increased the ZO-1/afadin interaction, while S1102A reduced this interaction during extracellular calcium-induced junction assembly. Inhibition of aPKCζ activity also increased the ZO-1/afadin interaction. Taken together, these data suggest that aPKCζ phosphorylation of afadin terminates the ZO-1/afadin interaction and thus permits the later stages of junction assembly.
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Affiliation(s)
- Jingshing Wu
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut
| | - Pascal Rowart
- Groupe Interdisciplinaire de Génoprotéomique Appliquée, Cardiovascular Sciences, University of Liège, Liège, Belgium
| | - Francois Jouret
- Groupe Interdisciplinaire de Génoprotéomique Appliquée, Cardiovascular Sciences, University of Liège, Liège, Belgium
| | - Brandon M Gassaway
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut.,Systems Biology Institute, Yale University, West Haven, Connecticut
| | - Vanathy Rajendran
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut
| | - Jesse Rinehart
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut.,Systems Biology Institute, Yale University, West Haven, Connecticut
| | - Michael J Caplan
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut
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16
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Are There Shared Mechanisms in the Pathophysiology of Different Clinical Forms of Laminitis and What Are the Implications for Prevention and Treatment? Vet Clin North Am Equine Pract 2019; 35:379-398. [PMID: 31126692 DOI: 10.1016/j.cveq.2019.04.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Laminitis is a consequence of primary disease processes elsewhere in the body. The key pathophysiologic events are insulin dysregulation in endocrinopathic laminitis, ischemia in supporting limb laminitis, and inflammation in sepsis-related laminitis. These apparently disparate mechanisms converge to cause lamellar attachment failure through epithelial cell adhesion loss and stretch, possibly mediated by common growth factor signaling pathways. Tissue damage through mechanical distraction, inflammation, pain, and a proliferative epithelial healing response are features of acute laminitis regardless of the cause. Preventive and treatment strategies based on knowledge of these unique and common mechanistic events are likely to improve clinical outcomes.
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17
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Hypercapnia Alters Alveolar Epithelial Repair by a pH-Dependent and Adenylate Cyclase-Mediated Mechanism. Sci Rep 2019; 9:349. [PMID: 30674971 PMCID: PMC6344503 DOI: 10.1038/s41598-018-36951-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 11/23/2018] [Indexed: 12/16/2022] Open
Abstract
Lung cell injury and repair is a hallmark of the acute respiratory distress syndrome (ARDS). Lung protective mechanical ventilation strategies in these patients may lead to hypercapnia (HC). Although HC has been explored in the clinical context of ARDS, its effect upon alveolar epithelial cell (AEC) wounding and repair remains poorly understood. We have previously reported that HC alters the likelihood of AEC repair by a pH-sensitive but otherwise unknown mechanism. Adenylate cyclase (AC) is an attractive candidate as a putative AEC CO2 sensor and effector as it is bicarbonate sensitive and controls key mediators of AEC repair. The effect of HC on AC activity and plasma membrane (PM) wound repair was measured in AEC type 1 exposed to normocapnia (NC, 40 Torr) or HC (80 Torr), ± tromethamine (THAM) or sodium bicarbonate (HCO3) ± AC probes in a micropuncture model of AEC injury relevant to ARDS. Intracellular pH and AC activity were measured and correlated with repair. HC decreased intracellular pH 0.56, cAMP by 37%, and absolute PM repair rate by 26%. Buffering or pharmacologic manipulation of AC reduced or reversed the effects of HC on AC activity (THAM 103%, HCO3 113% of NC cAMP, ns; Forskolin 168%, p < 0.05) and PM repair (THAM 87%, HCO3 108% of NC likelihood to repair, ns; Forskolin 160%, p < 0.01). These findings suggest AC to be a putative AEC CO2 sensor and modulator of AEC repair, and may have implications for future pharmacologic targeting of downstream messengers of the AC-cAMP axis in experimental models of ARDS.
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18
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Weber K, Casali C, Gaveglio V, Pasquaré S, Morel Gómez E, Parra L, Erjavec L, Perazzo C, Fernández Tome MC. TAG synthesis and storage under osmotic stress. A requirement for preserving membrane homeostasis in renal cells. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:1108-1120. [DOI: 10.1016/j.bbalip.2018.06.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 05/11/2018] [Accepted: 06/12/2018] [Indexed: 12/14/2022]
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19
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McCarthy CG, Wenceslau CF, Ogbi S, Szasz T, Webb RC. Toll-Like Receptor 9-Dependent AMPK α Activation Occurs via TAK1 and Contributes to RhoA/ROCK Signaling and Actin Polymerization in Vascular Smooth Muscle Cells. J Pharmacol Exp Ther 2018; 365:60-71. [PMID: 29348267 DOI: 10.1124/jpet.117.245746] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 01/17/2018] [Indexed: 01/06/2023] Open
Abstract
Traditionally, Toll-like receptor 9 (TLR9) signals through an MyD88-dependent cascade that results in proinflammatory gene transcription. Recently, it was reported that TLR9 also participates in a stress tolerance signaling cascade in nonimmune cells. In this noncanonical pathway, TLR9 binds to and inhibits sarcoplasmic/endoplasmic reticulum Ca2+-ATPase 2 (SERCA2), modulating intracellular calcium handling, and subsequently resulting in the activation of 5'-AMP-activated protein kinase α (AMPKα). We have previously reported that TLR9 causes increased contraction in isolated arteries; however, the mechanisms underlying this vascular dysfunction need to be further clarified. Therefore, we hypothesized that noncanonical TLR9 signaling was also present in vascular smooth muscle cells (VSMCs) and that it mediates enhanced contractile responses through SERCA2 inhibition. To test these hypotheses, aortic microsomes, aortic VSMCs, and isolated arteries from male Sprague-Dawley rats were incubated with vehicle or TLR9 agonist (ODN2395). Despite clear AMPKα activation after treatment with ODN2395, SERCA2 activity was unaffected. Alternatively, ODN2395 caused the phosphorylation of AMPKα via transforming growth factor β-activated kinase 1 (TAK1), a kinase involved in TLR9 inflammatory signaling. Downstream, we hypothesized that that TLR9 activation of AMPKα may be important in mediating actin cytoskeleton reorganization. ODN2395 significantly increased the filamentous-to-globular actin ratio, as well as indices of RhoA/Rho-associated protein kinase (ROCK) activation, with the latter being prevented by AMPKα inhibition. In conclusion, AMPKα phosphorylation after TLR9 activation in VSMCs appears to be an extension of traditional inflammatory signaling via TAK1, as opposed to SERCA2 inhibition and the noncanonical pathway. Nonetheless, TLR9-AMPKα signaling can mediate VSMC function via RhoA/ROCK activation and actin polymerization.
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Affiliation(s)
| | | | - Safia Ogbi
- Department of Physiology, Augusta University, Augusta, Georgia
| | - Theodora Szasz
- Department of Physiology, Augusta University, Augusta, Georgia
| | - R Clinton Webb
- Department of Physiology, Augusta University, Augusta, Georgia
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20
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Martin E, Bonnamour G, Jenna S. AMPK and autophagy control embryonic elongation as part of a RhoA-like morphogenic program in nematode. Small GTPases 2017; 11:186-193. [PMID: 29172954 DOI: 10.1080/21541248.2017.1372868] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
Autophagy is the process where cytosolic components are digested by the cell. This process is required for cell survival in stressful conditions. It was also shown to control cell division and more recently, cell morphology and migration. We characterized signalling pathways enabling embryonic epidermal cells of the nematode Caenorhabditis elegans to elongate along their antero-posterior axis. Previous studies revealed that epidermal cells can adopt either a RhoA-like or a Rac1-like morphogenic program. We show here that the AMP-activated protein kinase (AMPK) and genes controlling autophagy are required for proper elongation of epidermal cells following the RhoA-like program and are dispensable for other cells. This suggests that AMPK-autophagy is used by the embryo to fuel the most energy-demanding morphogenic processes promoting early elongation.
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Affiliation(s)
- Emmanuel Martin
- Integrative Genomics and cell signaling laboratory, Chemistry-Biochemistry Department, Université du Québec à Montréal (UQAM), Montreal, Canada
| | - Grégoire Bonnamour
- Integrative Genomics and cell signaling laboratory, Chemistry-Biochemistry Department, Université du Québec à Montréal (UQAM), Montreal, Canada
| | - Sarah Jenna
- Integrative Genomics and cell signaling laboratory, Chemistry-Biochemistry Department, Université du Québec à Montréal (UQAM), Montreal, Canada
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21
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Zhu H, Yang H, Zhao S, Zhang J, Liu D, Tian Y, Shen Z, Su Y. Role of the cofilin 2 gene in regulating the myosin heavy chain genes in mouse myoblast C2C12 cells. Int J Mol Med 2017; 41:1096-1102. [PMID: 29207028 DOI: 10.3892/ijmm.2017.3272] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 11/15/2017] [Indexed: 11/06/2022] Open
Abstract
The cofilin 2 (CFL2) and myosin heavy chain (MyHC) genes play a key role in muscle development and myofibrillar formation. The aim of the present study was to investigate the effect of CFL2 on genes involved in fiber formation and the mechanisms underlying this process. Undifferentiated and differentiated C2C12 cells (UDT and DT, respectively) were transfected with CFL2 small interfering RNA (siRNA). CFL2 mRNA and protein levels were assessed using reverse transcription polymerase chain reaction (RT-PCR) and western blotting, respectively. MyHC gene expression in UDT and signaling pathway-related factors were observed with quantitative PCR (RT‑qPCR) and western blotting. Fluorescence microscopy was used to analyze the cytoskeletal effects of CFL2. The mRNA and protein expressions of CFL2, four MyHC isoforms (MyHC-I, MyHC-IIa, MyHC-IIb and MyHC-IIx), p38 mitogen-activated protein kinase, cAMP-response element-binding protein, AMP-activated protein kinase α1, and myocyte enhancer factor 2C, were significantly decreased in UDT. However, extracellular signal-regulated kinase 2 expression was significantly increased. Slightly decreased CFL2 protein and mRNA expression was observed in DT C2C12 cells transfected with CFL2 siRNA. Fluorescence microscopy revealed a significant decrease of CFL2 in the cytoplasm, but not the nucleus, of UDT, compared with normal cells. These results indicated that the mouse CFL2 gene may be involved in the regulation of MyHC via the key signaling molecules of CFL2-related signaling pathways.
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Affiliation(s)
- Hongyan Zhu
- College of Animal Science and Veterinary Medicine, Jinzhou Medical University, Jinzhou, Liaoning 121001, P.R. China
| | - Huixin Yang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu 210000, P.R. China
| | - Song Zhao
- Central Laboratary, Jinzhou Medical University, Jinzhou, Liaoning 121001, P.R. China
| | - Junfeng Zhang
- College of Animal Science and Veterinary Medicine, Jinzhou Medical University, Jinzhou, Liaoning 121001, P.R. China
| | - Dan Liu
- College of Animal Science and Veterinary Medicine, Jinzhou Medical University, Jinzhou, Liaoning 121001, P.R. China
| | - Yumin Tian
- College of Animal Science and Veterinary Medicine, Jinzhou Medical University, Jinzhou, Liaoning 121001, P.R. China
| | - Zhiyi Shen
- College of Animal Science and Veterinary Medicine, Jinzhou Medical University, Jinzhou, Liaoning 121001, P.R. China
| | - Yuhong Su
- College of Animal Science and Veterinary Medicine, Jinzhou Medical University, Jinzhou, Liaoning 121001, P.R. China
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22
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Moreira D, Silvestre R, Cordeiro-da-Silva A, Estaquier J, Foretz M, Viollet B. AMP-activated Protein Kinase As a Target For Pathogens: Friends Or Foes? Curr Drug Targets 2017; 17:942-53. [PMID: 25882224 DOI: 10.2174/1389450116666150416120559] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 03/24/2015] [Accepted: 04/10/2015] [Indexed: 12/21/2022]
Abstract
Intracellular pathogens are known to manipulate host cell regulatory pathways to establish an optimal environment for their growth and survival. Pathogens employ active mechanisms to hijack host cell metabolism and acquire existing nutrient and energy store. The role of the cellular energy sensor AMP-activated protein kinase (AMPK) in the regulation of cellular energy homeostasis is well documented. Here, we highlight recent advances showing the importance of AMPK signaling in pathogen-host interactions. Pathogens interact with AMPK by a variety of mechanisms aimed at reprogramming host cell metabolism to their own benefit. Stimulation of AMPK activity provides an efficient process to rapidly adapt pathogen metabolism to the major nutritional changes often encountered during the different phases of infection. However, inhibition of AMPK is also used by pathogens to manipulate innate host response, indicating that AMPK appears relevant to restriction of pathogen infection. We also document the effects of pharmacological AMPK modulators on pathogen proliferation and survival. This review illustrates intricate pathogen-AMPK interactions that may be exploited to the development of novel anti-pathogen therapies.
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Affiliation(s)
| | | | | | | | | | - Benoit Viollet
- Institut Cochin, Inserm U1016, CNRS UMR8104, Université Paris Descartes, 24 rue du faubourg Saint Jacques 75014 Paris, France.
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23
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AMP-activated protein kinase/myocardin-related transcription factor-A signaling regulates fibroblast activation and renal fibrosis. Kidney Int 2017; 93:81-94. [PMID: 28739141 DOI: 10.1016/j.kint.2017.04.033] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 04/22/2017] [Accepted: 04/28/2017] [Indexed: 01/19/2023]
Abstract
Chronic kidney disease is a major cause of death, and renal fibrosis is a common pathway leading to the progression of this disease. Although activated fibroblasts are responsible for the production of the extracellular matrix and the development of renal fibrosis, the molecular mechanisms underlying fibroblast activation are not fully defined. Here we examined the functional role of AMP-activated protein kinase (AMPK) in the activation of fibroblasts and the development of renal fibrosis. AMPKα1 was induced in the kidney during the development of renal fibrosis. Mice with global or fibroblast-specific knockout of AMPKα1 exhibited fewer myofibroblasts, developed less fibrosis, and produced less extracellular matrix protein in the kidneys following unilateral ureteral obstruction or ischemia-reperfusion injury. Mechanistically, AMPKα1 directly phosphorylated cofilin leading to cytoskeleton remodeling and myocardin-related transcription factor-A nuclear translocation resulting in fibroblast activation and extracellular matrix protein production. Thus, AMPK may be a critical regulator of fibroblast activation through regulation of cytoskeleton dynamics and myocardin-related transcription factor-A nuclear translocation. Hence, AMPK signaling may represent a novel therapeutic target for fibrotic kidney disease.
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24
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Schubert KM, Qiu J, Blodow S, Wiedenmann M, Lubomirov LT, Pfitzer G, Pohl U, Schneider H. The AMP-Related Kinase (AMPK) Induces Ca
2+
-Independent Dilation of Resistance Arteries by Interfering With Actin Filament Formation. Circ Res 2017; 121:149-161. [DOI: 10.1161/circresaha.116.309962] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 05/23/2017] [Accepted: 06/06/2017] [Indexed: 12/13/2022]
Abstract
Rationale:
Decreasing Ca
2+
sensitivity of vascular smooth muscle (VSM) allows for vasodilation without lowering of cytosolic Ca
2+
. This may be particularly important in states requiring maintained dilation, such as hypoxia. AMP-related kinase (AMPK) is an important cellular energy sensor in VSM. Regulation of Ca
2+
sensitivity usually is attributed to myosin light chain phosphatase activity, but findings in non-VSM identified changes in the actin cytoskeleton. The potential role of AMPK in this setting is widely unknown.
Objective:
To assess the influence of AMPK on the actin cytoskeleton in VSM of resistance arteries with regard to potential Ca
2+
desensitization of VSM contractile apparatus.
Methods and Results:
AMPK induced a slowly developing dilation at unchanged cytosolic Ca
2+
levels in potassium chloride–constricted intact arteries isolated from mouse mesenteric tissue. This dilation was not associated with changes in phosphorylation of myosin light chain or of myosin light chain phosphatase regulatory subunit. Using ultracentrifugation and confocal microscopy, we found that AMPK induced depolymerization of F-actin (filamentous actin). Imaging of arteries from LifeAct mice showed F-actin rarefaction in the midcellular portion of VSM. Immunoblotting revealed that this was associated with activation of the actin severing factor cofilin. Coimmunoprecipitation experiments indicated that AMPK leads to the liberation of cofilin from 14-3-3 protein.
Conclusions:
AMPK induces actin depolymerization, which reduces vascular tone and the response to vasoconstrictors. Our findings demonstrate a new role of AMPK in the control of actin cytoskeletal dynamics, potentially allowing for long-term dilation of microvessels without substantial changes in cytosolic Ca
2+
.
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Affiliation(s)
- Kai Michael Schubert
- From the Walter Brendel Centre of Experimental Medicine, Biomedical Center of LMU, Ludwig Maximilian University of Munich, Germany (K.M.S., J.Q., S.B., M.W., U.P., H.S.); Munich Cluster for Systems Neurology (SyNergy), Germany (K.M.S., S.B., U.P., H.S.); Deutsches Zentrum für Herz- Kreislauf-Forschung (German Center for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich, Germany (K.M.S., S.B., U.P., H.S.); and Institute of Vegetative Physiology, University of Cologne, Germany (L.T
| | - Jiehua Qiu
- From the Walter Brendel Centre of Experimental Medicine, Biomedical Center of LMU, Ludwig Maximilian University of Munich, Germany (K.M.S., J.Q., S.B., M.W., U.P., H.S.); Munich Cluster for Systems Neurology (SyNergy), Germany (K.M.S., S.B., U.P., H.S.); Deutsches Zentrum für Herz- Kreislauf-Forschung (German Center for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich, Germany (K.M.S., S.B., U.P., H.S.); and Institute of Vegetative Physiology, University of Cologne, Germany (L.T
| | - Stephanie Blodow
- From the Walter Brendel Centre of Experimental Medicine, Biomedical Center of LMU, Ludwig Maximilian University of Munich, Germany (K.M.S., J.Q., S.B., M.W., U.P., H.S.); Munich Cluster for Systems Neurology (SyNergy), Germany (K.M.S., S.B., U.P., H.S.); Deutsches Zentrum für Herz- Kreislauf-Forschung (German Center for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich, Germany (K.M.S., S.B., U.P., H.S.); and Institute of Vegetative Physiology, University of Cologne, Germany (L.T
| | - Margarethe Wiedenmann
- From the Walter Brendel Centre of Experimental Medicine, Biomedical Center of LMU, Ludwig Maximilian University of Munich, Germany (K.M.S., J.Q., S.B., M.W., U.P., H.S.); Munich Cluster for Systems Neurology (SyNergy), Germany (K.M.S., S.B., U.P., H.S.); Deutsches Zentrum für Herz- Kreislauf-Forschung (German Center for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich, Germany (K.M.S., S.B., U.P., H.S.); and Institute of Vegetative Physiology, University of Cologne, Germany (L.T
| | - Lubomir T. Lubomirov
- From the Walter Brendel Centre of Experimental Medicine, Biomedical Center of LMU, Ludwig Maximilian University of Munich, Germany (K.M.S., J.Q., S.B., M.W., U.P., H.S.); Munich Cluster for Systems Neurology (SyNergy), Germany (K.M.S., S.B., U.P., H.S.); Deutsches Zentrum für Herz- Kreislauf-Forschung (German Center for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich, Germany (K.M.S., S.B., U.P., H.S.); and Institute of Vegetative Physiology, University of Cologne, Germany (L.T
| | - Gabriele Pfitzer
- From the Walter Brendel Centre of Experimental Medicine, Biomedical Center of LMU, Ludwig Maximilian University of Munich, Germany (K.M.S., J.Q., S.B., M.W., U.P., H.S.); Munich Cluster for Systems Neurology (SyNergy), Germany (K.M.S., S.B., U.P., H.S.); Deutsches Zentrum für Herz- Kreislauf-Forschung (German Center for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich, Germany (K.M.S., S.B., U.P., H.S.); and Institute of Vegetative Physiology, University of Cologne, Germany (L.T
| | - Ulrich Pohl
- From the Walter Brendel Centre of Experimental Medicine, Biomedical Center of LMU, Ludwig Maximilian University of Munich, Germany (K.M.S., J.Q., S.B., M.W., U.P., H.S.); Munich Cluster for Systems Neurology (SyNergy), Germany (K.M.S., S.B., U.P., H.S.); Deutsches Zentrum für Herz- Kreislauf-Forschung (German Center for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich, Germany (K.M.S., S.B., U.P., H.S.); and Institute of Vegetative Physiology, University of Cologne, Germany (L.T
| | - Holger Schneider
- From the Walter Brendel Centre of Experimental Medicine, Biomedical Center of LMU, Ludwig Maximilian University of Munich, Germany (K.M.S., J.Q., S.B., M.W., U.P., H.S.); Munich Cluster for Systems Neurology (SyNergy), Germany (K.M.S., S.B., U.P., H.S.); Deutsches Zentrum für Herz- Kreislauf-Forschung (German Center for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich, Germany (K.M.S., S.B., U.P., H.S.); and Institute of Vegetative Physiology, University of Cologne, Germany (L.T
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Ryu JH, Sung J, Xie C, Shin MK, Kim CW, Kim NG, Choi YJ, Choi BD, Kang SS, Kang D. Aplysia kurodai -derived glycosaminoglycans increase the phagocytic ability of macrophages via the activation of AMP-activated protein kinase and cytoskeletal reorganization in RAW264.7 cells. J Funct Foods 2016. [DOI: 10.1016/j.jff.2016.08.059] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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26
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Chakrabarti KR, Whipple RA, Boggs AE, Hessler LK, Bhandary L, Vitolo MI, Thompson K, Martin SS. Pharmacologic regulation of AMPK in breast cancer affects cytoskeletal properties involved with microtentacle formation and re-attachment. Oncotarget 2016; 6:36292-307. [PMID: 26431377 PMCID: PMC4742178 DOI: 10.18632/oncotarget.5345] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 09/11/2015] [Indexed: 01/20/2023] Open
Abstract
The presence of tumor cells in the circulation is associated with a higher risk of metastasis in patients with breast cancer. Circulating breast tumor cells use tubulin-based structures known as microtentacles (McTNs) to re-attach to endothelial cells and arrest in distant organs. McTN formation is dependent on the opposing cytoskeletal forces of stable microtubules and the actin network. AMP-activated protein kinase (AMPK) is a cellular metabolic regulator that can alter actin and microtubule organization in epithelial cells. We report that AMPK can regulate the cytoskeleton of breast cancer cells in both attached and suspended conditions. We tested the effects of AMPK on microtubule stability and the actin-severing protein, cofilin. AMPK inhibition with compound c increased both microtubule stability and cofilin activation, which also resulted in higher McTN formation and re-attachment. Conversely, AMPK activation with A-769662 decreased microtubule stability and cofilin activation with concurrent decreases in McTN formation and cell re-attachment. This data shows for the first time that AMPK shifts the balance of cytoskeletal forces in suspended breast cancer cells, which affect their ability to form McTNs and re-attach. These results support a model where AMPK activators may be used therapeutically to reduce the metastatic efficiency of breast tumor cells.
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Affiliation(s)
- Kristi R Chakrabarti
- University of Maryland School of Medicine, Marlene and Stewart Greenebaum National Cancer Institute Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA.,Graduate Program in Molecular Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Rebecca A Whipple
- University of Maryland School of Medicine, Marlene and Stewart Greenebaum National Cancer Institute Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Amanda E Boggs
- University of Maryland School of Medicine, Marlene and Stewart Greenebaum National Cancer Institute Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA.,Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Lindsay K Hessler
- University of Maryland School of Medicine, Marlene and Stewart Greenebaum National Cancer Institute Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Lekhana Bhandary
- University of Maryland School of Medicine, Marlene and Stewart Greenebaum National Cancer Institute Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA.,Graduate Program in Molecular Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Michele I Vitolo
- University of Maryland School of Medicine, Marlene and Stewart Greenebaum National Cancer Institute Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA.,Graduate Program in Molecular Medicine, University of Maryland School of Medicine, Baltimore, MD, USA.,Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Keyata Thompson
- University of Maryland School of Medicine, Marlene and Stewart Greenebaum National Cancer Institute Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Stuart S Martin
- University of Maryland School of Medicine, Marlene and Stewart Greenebaum National Cancer Institute Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA.,Graduate Program in Molecular Medicine, University of Maryland School of Medicine, Baltimore, MD, USA.,Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
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27
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Creuzet SE, Viallet JP, Ghawitian M, Torch S, Thélu J, Alrajeh M, Radu AG, Bouvard D, Costagliola F, Borgne ML, Buchet-Poyau K, Aznar N, Buschlen S, Hosoya H, Thibert C, Billaud M. LKB1 signaling in cephalic neural crest cells is essential for vertebrate head development. Dev Biol 2016; 418:283-96. [DOI: 10.1016/j.ydbio.2016.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 07/19/2016] [Accepted: 08/06/2016] [Indexed: 11/25/2022]
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28
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Dopie J, Rajakylä EK, Joensuu MS, Huet G, Ferrantelli E, Xie T, Jäälinoja H, Jokitalo E, Vartiainen MK. Genome-wide RNAi screen for nuclear actin reveals a network of cofilin regulators. J Cell Sci 2015; 128:2388-400. [PMID: 26021350 PMCID: PMC4510847 DOI: 10.1242/jcs.169441] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 05/19/2015] [Indexed: 01/15/2023] Open
Abstract
Nuclear actin plays an important role in many processes that regulate gene expression. Cytoplasmic actin dynamics are tightly controlled by numerous actin-binding proteins, but regulation of nuclear actin has remained unclear. Here, we performed a genome-wide RNA interference (RNAi) screen in Drosophila cells to identify proteins that influence either nuclear polymerization or import of actin. We validate 19 factors as specific hits, and show that Chinmo (known as Bach2 in mammals), SNF4Aγ (Prkag1 in mammals) and Rab18 play a role in nuclear localization of actin in both fly and mammalian cells. We identify several new regulators of cofilin activity, and characterize modulators of both cofilin kinases and phosphatase. For example, Chinmo/Bach2, which regulates nuclear actin levels also in vivo, maintains active cofilin by repressing the expression of the kinase Cdi (Tesk in mammals). Finally, we show that Nup98 and lamin are candidates for regulating nuclear actin polymerization. Our screen therefore reveals new aspects of actin regulation and links nuclear actin to many cellular processes.
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Affiliation(s)
- Joseph Dopie
- Program in Cell and Molecular Biology, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Eeva K Rajakylä
- Program in Cell and Molecular Biology, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Merja S Joensuu
- Program in Cell and Molecular Biology, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Guillaume Huet
- Program in Cell and Molecular Biology, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Evelina Ferrantelli
- Program in Cell and Molecular Biology, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Tiao Xie
- Image and Data Analysis Core (IDAC), Harvard Medical School, Boston, MA 02115, USA
| | - Harri Jäälinoja
- Light Microscopy Unit, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - Eija Jokitalo
- Program in Cell and Molecular Biology, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland Electron Microscopy Unit, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Maria K Vartiainen
- Program in Cell and Molecular Biology, Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
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Abstract
Adenosine monophosphate-activated protein kinase (AMPK) is a serine/threonine kinase that is crucial for cellular energy metabolism homeostasis. AMPK monitors cellular energy status in response to nutritional variations and, once activated by low energy status, switches on ATP-producing catabolic pathways and switches off ATP-consuming anabolic pathways to restore cellular energy homeostasis. When T lymphocytes encounter foreign antigens, they initiate a program of differentiation leading to the rapid generation of effector and memory cells that clear the pathogen and prevent future infection, respectively. Differentiation of naïve T cells in effector or long term memory cells is tightly associated with changes in their energy metabolic activity and recent data have revealed that fine-tuning of metabolism could modulate T cell functions. Here, we will review recent data about the regulation of T cell metabolism by AMPK and discuss its influence on T cell function.
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Affiliation(s)
- Fabienne Andris
- Laboratoire d'Immunobiologie, Institut de Biologie et de Médecine Moléculaire, Université Libre de Bruxelles, Gosselies, Belgium
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30
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Le Dréan G, Segain JP. Connecting metabolism to intestinal barrier function: The role of leptin. Tissue Barriers 2014; 2:e970940. [PMID: 25610758 DOI: 10.4161/21688362.2014.970940] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 09/25/2014] [Indexed: 12/16/2022] Open
Abstract
Structure and function of the intestinal epithelial barrier (IEB) are dependent upon the integrity of junctional protein structures sealing the apical surface between epithelial cells. Tight junctions (TJ) and the surrounding apical F-actin cytoskeleton are involved in the regulation of paracellular permeability. The regulation of actin cytoskeleton organization by RhoA/Rho-kinase (ROCK) pathway plays an important role in TJ assembly and function. There is mounting evidence that the adipocyte-derived hormone leptin exerts pleiotropic effects on the intestinal epithelium including nutrient absorption, epithelial growth, inflammation and injury. Leptin activates multiple cell signaling pathways in intestinal epithelial cells (IEC) that can explain these pleiotropic effects. However, these pathways are also involved in the primary role of leptin that is the regulation of energy and glucose metabolism homeostasis. In this commentary, we examine how the interplay between leptin signaling pathways that regulate cell metabolism could impact upon IEB function.
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Key Words
- AMPK
- AMPK, AMP-activated protein kinase
- IEB, intestinal epithelial barrier
- IEC, intestinal epithelial cells
- JAK, Janus kinase
- JAK/STAT
- LepR-b, leptin receptor
- MEF, mouse embryonic fibroblast
- MLC, myosin light chain
- ROCK, Rho-kinase
- RhoA/ROCK
- STAT, signal transducer and activator of transcription
- TJ, tight junctions
- VAT, visceral adipose tissue
- barrier repair
- intestinal epithelial barrier
- leptin
- metabolism
- tight-junction
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Affiliation(s)
- Gwenola Le Dréan
- Université de Nantes; Institut des Maladies de l'Appareil Digestif (IMAD); Centre de Recherche en Nutrition Humaine du Grand Ouest (CRNH) ; Nantes, France ; CHU Hôtel-Dieu, Place Alexis Ricordeau ; Nantes, France
| | - Jean-Pierre Segain
- Université de Nantes; Institut des Maladies de l'Appareil Digestif (IMAD); Centre de Recherche en Nutrition Humaine du Grand Ouest (CRNH) ; Nantes, France ; CHU Hôtel-Dieu, Place Alexis Ricordeau ; Nantes, France
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Sid B, Glorieux C, Valenzuela M, Rommelaere G, Najimi M, Dejeans N, Renard P, Verrax J, Calderon PB. AICAR induces Nrf2 activation by an AMPK-independent mechanism in hepatocarcinoma cells. Biochem Pharmacol 2014; 91:168-80. [PMID: 25058527 DOI: 10.1016/j.bcp.2014.07.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 07/14/2014] [Accepted: 07/15/2014] [Indexed: 02/07/2023]
Abstract
Hepatocellular carcinoma is one of the most frequent tumor types worldwide and oxidative stress represents a major risk factor in pathogenesis of liver diseases leading to HCC. Nuclear factor erythroid 2-related factor (Nrf2) is a transcription factor activated by oxidative stress that governs the expression of many genes which constitute the antioxidant defenses of the cell. In addition, oxidative stress activates AMP-activated protein kinase (AMPK), which has emerged in recent years as a kinase that controls the redox-state of the cell. Since both AMPK and Nrf2 are involved in redox homeostasis, we investigated whether there was a crosstalk between the both signaling systems in hepatocarcinoma cells. Here, we demonstrated that AMPK activator AICAR, in contrary to the A769662 allosteric activator, induces Nrf2 activation and concomitantly modulates the basal redox state of the hepatocarcinoma cells. When the expression of Nrf2 is knocked down, AICAR failed to induce its effect on redox state. These data highlight a major role of Nrf2 signaling pathway in mediating the AICAR effect on basal oxidative state. Furthermore, we demonstrated that AICAR metabolization by the cell is required to induce Nrf2 activation while, the silencing of AMPK does not have any effect on Nrf2 activation. This suggests that AICAR-induced Nrf2 activation is independent of AMPK activity. In conclusion, we identified AICAR as a potent modulator of the redox state of human hepatocarcinoma cells, via the Nrf2 signaling pathway and in an AMPK-independent mechanism.
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Affiliation(s)
- Brice Sid
- Toxicology and Cancer Biology Research Group GTOX, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Christophe Glorieux
- Toxicology and Cancer Biology Research Group GTOX, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Manuel Valenzuela
- Toxicology and Cancer Biology Research Group GTOX, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Guillaume Rommelaere
- Laboratory of Biochemistry and Cell Biology (URBC), NARILIS (NAmur Research Institute for Life Sciences), University of Namur (UNamur), Namur, Belgium
| | - Mustapha Najimi
- Laboratory of Pediatric Hepatology and Cell Therapy, Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain, Brussels, Belgium
| | - Nicolas Dejeans
- Toxicology and Cancer Biology Research Group GTOX, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Patricia Renard
- Laboratory of Biochemistry and Cell Biology (URBC), NARILIS (NAmur Research Institute for Life Sciences), University of Namur (UNamur), Namur, Belgium
| | - Julien Verrax
- Toxicology and Cancer Biology Research Group GTOX, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Pedro Buc Calderon
- Toxicology and Cancer Biology Research Group GTOX, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium; Facultad de Ciencias de la Salud, Universidad Arturo Prat, Iquique, Chile.
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Onselaer MB, Oury C, Hunter RW, Eeckhoudt S, Barile N, Lecut C, Morel N, Viollet B, Jacquet LM, Bertrand L, Sakamoto K, Vanoverschelde JL, Beauloye C, Horman S. The Ca(2+) /calmodulin-dependent kinase kinase β-AMP-activated protein kinase-α1 pathway regulates phosphorylation of cytoskeletal targets in thrombin-stimulated human platelets. J Thromb Haemost 2014; 12:973-86. [PMID: 24655923 DOI: 10.1111/jth.12568] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Indexed: 12/14/2022]
Abstract
BACKGROUND Platelet activation requires sweeping morphologic changes, supported by contraction and remodeling of the platelet actin cytoskeleton. In various other cell types, AMP-activated protein kinase (AMPK) controls the phosphorylation state of cytoskeletal targets. OBJECTIVE To determine whether AMPK is activated during platelet aggregation and contributes to the control of cytoskeletal targets. RESULTS We found that AMPK-α1 was mainly activated by thrombin, and not by other platelet agonists, in purified human platelets. Thrombin activated AMPK-α1 ex vivo via a Ca(2+) /calmodulin-dependent kinase kinase β (CaMKKβ)-dependent pathway. Pharmacologic inhibition of CaMKKβ blocked thrombin-induced platelet aggregation and counteracted thrombin-induced phosphorylation of several cytoskeletal proteins, namely, regulatory myosin light chains (MLCs), cofilin, and vasodilator-stimulated phosphoprotein (VASP), three key elements involved in actin cytoskeletal contraction and polymerization. Platelets isolated from mice lacking AMPK-α1 showed reduced aggregation in response to thrombin, and this was associated with defects in MLC, cofilin and VASP phosphorylation and actin polymerization. More importantly, we show, for the first time, that the AMPK pathway is activated in platelets of patients undergoing major cardiac surgery, in a heparin-sensitive manner. CONCLUSION AMPK-α1 is activated by thrombin in human platelets. It controls the phosphorylation of key cytoskeletal targets and actin cytoskeletal remodeling during platelet aggregation.
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Affiliation(s)
- M-B Onselaer
- Institut de Recherche Expérimentale et Clinique (IREC), Pôle de Recherche Cardiovasculaire, Université catholique de Louvain, Brussels, Belgium
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33
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Randriamboavonjy V, Fleming I. Energy and motion: AMP-activated protein kinase α1 and its role in platelet activation. J Thromb Haemost 2014; 12:970-2. [PMID: 24738639 DOI: 10.1111/jth.12584] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Indexed: 11/30/2022]
Affiliation(s)
- V Randriamboavonjy
- Center for Molecular Medicine, Institute for Vascular Signaling, Goethe University, Frankfurt am Main, Germany
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34
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Burns TA, Watts MR, Weber PS, McCutcheon LJ, Geor RJ, Belknap JK. Effect of dietary nonstructural carbohydrate content on activation of 5'-adenosine monophosphate-activated protein kinase in liver, skeletal muscle, and digital laminae of lean and obese ponies. J Vet Intern Med 2014; 28:1280-8. [PMID: 24750267 PMCID: PMC4857936 DOI: 10.1111/jvim.12356] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 12/13/2013] [Accepted: 03/05/2014] [Indexed: 01/16/2023] Open
Abstract
Background In EMS‐associated laminitis, laminar failure may occur in response to energy failure related to insulin resistance (IR) or to the effect of hyperinsulinemia on laminar tissue. 5′‐Adenosine‐monophosphate‐activated protein kinase (AMPK) is a marker of tissue energy deprivation, which may occur in IR. Hypothesis/Objectives To characterize tissue AMPK regulation in ponies subjected to a dietary carbohydrate (CHO) challenge. Animals Twenty‐two mixed‐breed ponies. Methods Immunohistochemistry and immunoblotting for total AMPK and phospho(P)‐AMPK and RT‐qPCR for AMPK‐responsive genes were performed on laminar, liver, and skeletal muscle samples collected after a 7‐day feeding protocol in which ponies stratified on body condition score (BCS; obese or lean) were fed either a low‐CHO diet (ESC + starch, approximately 7% DM; n = 5 obese, 5 lean) or a high‐CHO diet (ESC + starch, approximately 42% DM; n = 6 obese, 6 lean). Results 5′‐Adenosine‐monophosphate‐activated protein kinase was immunolocalized to laminar keratinocytes, dermal constituents, and hepatocytes. A high‐CHO diet resulted in significantly decreased laminar [P‐AMPK] in lean ponies (P = .03), but no changes in skeletal muscle (lean, P = .33; obese, P = .43) or liver (lean, P = .84; obese, P = .13) [P‐AMPK]. An inverse correlation existed between [blood glucose] and laminar [P‐AMPK] in obese ponies on a high‐CHO diet. Conclusions and Clinical Importance Laminar tissue exhibited a normal response to a high‐CHO diet (decreased [P‐AMPK]), whereas this response was not observed in liver and skeletal muscle in both lean (skeletal muscle, P = .33; liver, P = .84) and obese (skeletal muscle, P = .43; liver, P = .13) ponies.
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Affiliation(s)
- T A Burns
- The Ohio State University College of Veterinary Medicine, Columbus, OH
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Interactome analysis of AMP-activated protein kinase (AMPK)-α1 and -β1 in INS-1 pancreatic beta-cells by affinity purification-mass spectrometry. Sci Rep 2014; 4:4376. [PMID: 24625528 PMCID: PMC3953747 DOI: 10.1038/srep04376] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 02/26/2014] [Indexed: 12/23/2022] Open
Abstract
The heterotrimeric enzyme AMP-activated protein kinase (AMPK) is a major metabolic factor that regulates the homeostasis of cellular energy. In particular, AMPK mediates the insulin resistance that is associated with type 2 diabetes. Generally, cellular processes require tight regulation of protein kinases, which is effected through their formation of complex with other proteins and substrates. Despite their critical function in regulation and pathogenesis, there are limited data on the interaction of protein kinases. To identify proteins that interact with AMPK, we performed large-scale affinity purification (AP)-mass spectrometry (MS) of the AMPK-α1 and -β1 subunits. Through a comprehensive analysis, using a combination of immunoprecipitaion and ion trap mass spectrometry, we identified 381 unique proteins in the AMPKα/β interactomes: 325 partners of AMPK-α1 and 243 for AMPK-β1. Further, we identified 196 novel protein-protein interactions with AMPK-α1 and AMPK-β1. Notably, in our bioinformatics analysis, the novel interaction partners mediated functions that are related to the regulation of actin organization. Specifically, several such proteins were linked to pancreatic beta-cell functions, including glucose-stimulated insulin secretion, beta-cell development, beta-cell differentiation, and cell-cell communication.
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Garbutcheon-Singh KB, Myers S, Harper BWJ, Ng NS, Dong Q, Xie C, Aldrich-Wright JR. The effects of 56MESS on mitochondrial and cytoskeletal proteins and the cell cycle in MDCK cells. Metallomics 2014; 5:1061-7. [PMID: 23784536 DOI: 10.1039/c3mt00023k] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
BACKGROUND 56MESS has been shown to be cytotoxic but the mode of this action is unclear. In order to probe the mechanism of action for 56MESS, MDCK cells were utilised to investigate the effect on treated cells. RESULTS IC50 values for 56MESS and cisplatin in the MDCK cell line, determined by a SRB assay, were 0.25 ± 0.03 and 18 ± 1.2 μM respectively. In a preliminary study, cells treated with 56MESS displayed no caspase-3/7 activity, suggesting that the mechanism of action is caspase independent. Protein expression studies revealed an increase the expression in the MTC02 protein associated with mitochondria in cells treated with 56MESS and cisplatin. Non-synchronised 56MESS-treated cells caused an arrest in the G2/M phase of the cell cycle, in comparison to the S phase arrest of cisplatin. In G0/G1 synchronised cells, both 56MESS and cisplatin both appeared to arrest within the S phase. CONCLUSIONS these results suggest that 56MESS is capable of causing cell-cycle arrest, and that mitochondrial and cell cycle proteins may be involved in the mode of action of cytotoxicity of 56MESS.
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Affiliation(s)
- K Benjamin Garbutcheon-Singh
- Nanoscale Organisation and Dynamics Group, School of Science and Health, University of Western Sydney, Locked Bag 1797, Penrith South DC, NSW. 2751, Australia
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Connection between cardiac vascular permeability, myocardial edema, and inflammation during sepsis: role of the α1AMP-activated protein kinase isoform. Crit Care Med 2014; 41:e411-22. [PMID: 23963133 DOI: 10.1097/ccm.0b013e31829866dc] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
OBJECTIVE As adenosine monophosphate (AMP)-activated protein kinase both controls cytoskeleton organization in endothelial cells and exerts anti-inflammatory effects, we here postulated that it could influence vascular permeability and inflammation, thereby counteracting cardiac wall edema during sepsis. DESIGN Controlled animal study. SETTINGS University research laboratory. SUBJECTS C57BL/6J, α1AMPK, and α1AMPK mice. INTERVENTION Sepsis was triggered in vivo using a sublethal injection of lipopolysaccharide (O55B5, 10 mg/kg), inducing systolic left ventricular dysfunction. Left ventricular function, edema, vascular permeability, and inflammation were assessed in vivo in both wild-type mice (α1AMPK) and α1AMP-activated protein kinase-deficient mice (α1AMPK). The 5-aminoimidazole-4-carboxamide riboside served to study the impact of AMP-activated protein kinase activation on vascular permeability in vivo. The integrity of endothelial cell monolayers was also examined in vitro after lipopolysaccharide challenge in the presence of aminoimidazole-4-carboxamide riboside and/or after α1AMP-activated protein kinase silencing. MEASUREMENTS AND MAIN RESULTS α1AMP-activated protein kinase deficiency dramatically impaired tolerance to lipopolysaccharide challenge. Indeed, α1AMPK exhibited heightened cardiac vascular permeability after lipopolysaccharide challenge compared with α1AMPK. Consequently, an increase in left ventricular mass corresponding to exaggerated wall edema occurred in α1AMPK, without any further decrease in systolic function. Mechanistically, the lipopolysaccharide-induced α1AMPK cardiac phenotype could not be attributed to major changes in the systemic inflammatory response but was due to an increased disruption of interendothelial tight junctions. Accordingly, AMP-activated protein kinase activation by aminoimidazole-4-carboxamide riboside counteracted lipopolysaccharide-induced hyperpermeability in wild-type mice in vivo as well as in endothelial cells in vitro. This effect was associated with a potent protection of zonula occludens-1 linear border pattern in endothelial cells. CONCLUSIONS Our results demonstrate for the first time the involvement of a signaling pathway in the control of left ventricular wall edema during sepsis. AMP-activated protein kinase exerts a protective action through the preservation of interendothelial tight junctions. Interestingly, exaggerated left ventricular wall edema was not coupled with aggravated systolic dysfunction. However, it could contribute to diastolic dysfunction in patients with sepsis.
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de Meester C, Timmermans AD, Balteau M, Ginion A, Roelants V, Noppe G, Porporato PE, Sonveaux P, Viollet B, Sakamoto K, Feron O, Horman S, Vanoverschelde JL, Beauloye C, Bertrand L. Role of AMP-activated protein kinase in regulating hypoxic survival and proliferation of mesenchymal stem cells. Cardiovasc Res 2013; 101:20-9. [PMID: 24104879 DOI: 10.1093/cvr/cvt227] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
AIMS Mesenchymal stem cells (MSCs) are widely used for cell therapy, particularly for the treatment of ischaemic heart disease. Mechanisms underlying control of their metabolism and proliferation capacity, critical elements for their survival and differentiation, have not been fully characterized. AMP-activated protein kinase (AMPK) is a key regulator known to metabolically protect cardiomyocytes against ischaemic injuries and, more generally, to inhibit cell proliferation. We hypothesized that AMPK plays a role in control of MSC metabolism and proliferation. METHODS AND RESULTS MSCs isolated from murine bone marrow exclusively expressed the AMPKα1 catalytic subunit. In contrast to cardiomyocytes, a chronic exposure of MSCs to hypoxia failed to induce cell death despite the absence of AMPK activation. This hypoxic tolerance was the consequence of a preference of MSC towards glycolytic metabolism independently of oxygen availability and AMPK signalling. On the other hand, A-769662, a well-characterized AMPK activator, was able to induce a robust and sustained AMPK activation. We showed that A-769662-induced AMPK activation inhibited MSC proliferation. Proliferation was not arrested in MSCs derived from AMPKα1-knockout mice, providing genetic evidence that AMPK is essential for this process. Among AMPK downstream targets proposed to regulate cell proliferation, we showed that neither the p70 ribosomal S6 protein kinase/eukaryotic elongation factor 2-dependent protein synthesis pathway nor p21 was involved, whereas p27 expression was increased by A-769662. Silencing p27 expression partially prevented the A-769662-dependent inhibition of MSC proliferation. CONCLUSION MSCs resist hypoxia independently of AMPK whereas chronic AMPK activation inhibits MSC proliferation, p27 being involved in this regulation.
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Affiliation(s)
- Carole de Meester
- Pôle de Recherche Cardiovasculaire, Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Avenue Hippocrate, 55, B1.55.05, Brussels B-1200, Belgium
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Abstract
Insulin secretion from pancreatic β-cells is initiated by the closure of ATP-sensitive K+ channels (KATP) in response to high concentrations of glucose, and this action of glucose is counteracted by the hormone leptin, an adipokine that signals through the Ob-Rb receptor to increase KATP channel activity. Despite intensive investigations, the molecular basis for KATP channel regulation remains uncertain, particularly from the standpoint of whether fluctuations in plasma membrane KATP channel content underlie alterations of KATP channel activity in response to glucose or leptin. Surprisingly, newly published findings reveal that leptin stimulates AMP-activated protein kinase (AMPK) in order to promote trafficking of KATP channels from cytosolic vesicles to the plasma membrane of β-cells. This action of leptin is mimicked by low concentrations of glucose that also activate AMPK and that inhibit insulin secretion. Thus, a new paradigm for β-cell stimulus-secretion coupling is suggested in which leptin exerts a tonic inhibitory effect on β-cell excitability by virtue of its ability to increase plasma membrane KATP channel density and whole-cell KATP channel current. One important issue that remains unresolved is whether high concentrations of glucose suppress AMPK activity in order to shift the balance of membrane cycling so that KATP channel endocytosis predominates over vesicular KATP channel insertion into the plasma membrane. If so, high concentrations of glucose might transiently reduce KATP channel density/current, thereby favoring β-cell depolarization and insulin secretion. Such an AMPK-dependent action of glucose would complement its established ability to generate an increase of ATP/ADP concentration ratio that directly closes KATP channels in the plasma membrane.
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Affiliation(s)
- George G Holz
- Department of Medicine; State University of New York (SUNY); Upstate Medical University; Syracuse, NY USA
- Department of Pharmacology; State University of New York (SUNY); Upstate Medical University; Syracuse, NY USA
- Correspondence to: George G Holz,
| | - Oleg G Chepurny
- Department of Medicine; State University of New York (SUNY); Upstate Medical University; Syracuse, NY USA
| | - Colin A Leech
- Department of Medicine; State University of New York (SUNY); Upstate Medical University; Syracuse, NY USA
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40
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Sid B, Verrax J, Calderon PB. Role of AMPK activation in oxidative cell damage: Implications for alcohol-induced liver disease. Biochem Pharmacol 2013; 86:200-9. [PMID: 23688501 DOI: 10.1016/j.bcp.2013.05.007] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 05/03/2013] [Accepted: 05/08/2013] [Indexed: 02/08/2023]
Abstract
Chronic alcohol consumption is a well-known risk factor for liver disease. Progression of alcohol-induced liver disease (ALD) is a multifactorial process that involves a number of genetic, nutritional and environmental factors. Experimental and clinical studies increasingly show that oxidative damage induced by ethanol contributes in many ways to the pathogenesis of alcohol hepatoxicity. Oxidative stress appears to activate AMP-activated protein kinase (AMPK) signaling system, which has emerged in recent years as a kinase that controls the redox-state and mitochondrial function. This review focuses on the most recent insights concerning the activation of AMPK by reactive oxygen species (ROS), and describes recent evidences supporting the hypothesis that AMPK signaling pathways play an important role in promoting cell viability under conditions of oxidative stress, such as during alcohol exposure. We suggest that AMPK activation by ROS can promote cell survival by inducing autophagy, mitochondrial biogenesis and expression of genes involved in antioxidant defense. Hence, increased intracellular concentrations of ROS may represent a general mechanism for enhancement of AMPK-mediated cellular adaptation, including maintenance of redox homeostasis. On the other hand, AMPK inhibition in the liver by ethanol appears to play a key role in the development of steatosis induced by chronic alcohol consumption. Although more studies are needed to assess the functions of AMPK during oxidative stress, AMPK may be a possible therapeutic target in the particular case of alcohol-induced liver disease.
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Affiliation(s)
- Brice Sid
- Université Catholique de Louvain, Louvain Drug Research Institute, Toxicology and Cancer Biology Research Group GTOX, Brussels, Belgium
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41
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Stone JD, Narine A, Shaver PR, Fox JC, Vuncannon JR, Tulis DA. AMP-activated protein kinase inhibits vascular smooth muscle cell proliferation and migration and vascular remodeling following injury. Am J Physiol Heart Circ Physiol 2012. [PMID: 23203966 DOI: 10.1152/ajpheart.00446.2012] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Vascular smooth muscle cell (VSMC) activation promotes a synthetic phenotype that underlies many vessel growth disorders. In this regard it has been suggested that the metabolic sensor adenosine 5'-monophosphate-activated protein kinase (AMPK) has significant antigrowth and antimetastatic properties and may serve as a viable therapeutic target. In the current study we hypothesized that AMPK reduces neointima formation following balloon injury and that this occurs through reduction in VSMC proliferation and migration. Data reveal that local or systemic dosing with the AMPK agonist 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR) significantly increased AMPK activity in vivo and inhibited neointima formation in rat carotid arteries 2 wk after injury. In primary VSMCs, AICAR inhibited migration and induced cytostatic growth arrest through increased protein phosphatase 2A-mediated inhibition of mitosis-promoting cyclin B. AICAR also significantly enhanced AMPK-specific T278 phosphorylation of the actin anticapping vasodilator-activated serum phosphoprotein, increased G- to F-actin ratios and stress fiber formation, and abrogated PDGF-stimulated S397 autophosphorylation of focal adhesion kinase, promigratory cytoplasmic accumulation of paxillin, and extracellular matrix proteolysis by matrix metalloproteinase-9. Together, these results provide compelling evidence that AMPK serves to inhibit vascular smooth muscle migration and proliferation through regulation of cytoskeletal/focal adhesion/ECM stability, increasing our knowledge of this important metabolic regulator and providing support for its continued investigation in the treatment of vascular growth disorders.
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Affiliation(s)
- Joshua D Stone
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina 27834, USA
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42
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Siudeja K, Grzeschik NA, Rana A, de Jong J, Sibon OCM. Cofilin/Twinstar phosphorylation levels increase in response to impaired coenzyme a metabolism. PLoS One 2012; 7:e43145. [PMID: 22912811 PMCID: PMC3422318 DOI: 10.1371/journal.pone.0043145] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 07/19/2012] [Indexed: 11/19/2022] Open
Abstract
Coenzyme A (CoA) is a pantothenic acid-derived metabolite essential for many fundamental cellular processes including energy, lipid and amino acid metabolism. Pantothenate kinase (PANK), which catalyses the first step in the conversion of pantothenic acid to CoA, has been associated with a rare neurodegenerative disorder PKAN. However, the consequences of impaired PANK activity are poorly understood. Here we use Drosophila and human neuronal cell cultures to show how PANK deficiency leads to abnormalities in F-actin organization. Cells with reduced PANK activity are characterized by abnormally high levels of phosphorylated cofilin, a conserved actin filament severing protein. The increased levels of phospho-cofilin coincide with morphological changes of PANK-deficient Drosophila S2 cells and human neuronal SHSY-5Y cells. The latter exhibit also markedly reduced ability to form neurites in culture--a process that is strongly dependent on actin remodeling. Our results reveal a novel and conserved link between a metabolic biosynthesis pathway, and regulation of cellular actin dynamics.
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Affiliation(s)
| | | | | | | | - Ody C. M. Sibon
- Department of Cell Biology, Radiation and Stress Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
- * E-mail:
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43
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Brocker C, Thompson DC, Vasiliou V. The role of hyperosmotic stress in inflammation and disease. Biomol Concepts 2012; 3:345-364. [PMID: 22977648 PMCID: PMC3438915 DOI: 10.1515/bmc-2012-0001] [Citation(s) in RCA: 191] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hyperosmotic stress is an often overlooked process that potentially contributes to a number of human diseases. Whereas renal hyperosmolarity is a well-studied phenomenon, recent research provides evidence that many non-renal tissues routinely experience hyperosmotic stress that may contribute significantly to disease initiation and progression. Moreover, a growing body of evidence implicates hyperosmotic stress as a potent inflammatory stimulus by triggering proinflammatory cytokine release and inflammation. Under physiological conditions, the urine concentrating mechanism within the inner medullary region of the mammalian kidney exposes cells to high extracellular osmolarity. As such, renal cells have developed many adaptive strategies to compensate for increased osmolarity. Hyperosmotic stress is linked to many maladies, including acute and chronic, as well as local and systemic, inflammatory disorders. Hyperosmolarity triggers cell shrinkage, oxidative stress, protein carbonylation, mitochondrial depolarization, DNA damage, and cell cycle arrest, thus rendering cells susceptible to apoptosis. However, many adaptive mechanisms exist to counter the deleterious effects of hyperosmotic stress, including cytoskeletal rearrangement and up-regulation of antioxidant enzymes, transporters, and heat shock proteins. Osmolyte synthesis is also up-regulated and many of these compounds have been shown to reduce inflammation. The cytoprotective mechanisms and associated regulatory pathways that accompany the renal response to hyperosmolarity are found in many non-renal tissues, suggesting cells are commonly confronted with hyperosmotic conditions. Osmoadaptation allows cells to survive and function under potentially cytotoxic conditions. This review covers the pathological consequences of hyperosmotic stress in relation to disease and emphasizes the importance of considering hyperosmolarity in inflammation and disease progression.
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Affiliation(s)
- Chad Brocker
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - David C. Thompson
- Department of Clinical Pharmacy, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Vasilis Vasiliou
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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44
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Chan O, Burke JD, Gao DF, Fish EN. The chemokine CCL5 regulates glucose uptake and AMP kinase signaling in activated T cells to facilitate chemotaxis. J Biol Chem 2012; 287:29406-16. [PMID: 22782897 DOI: 10.1074/jbc.m112.348946] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Recruitment of effector T cells to sites of infection or inflammation is essential for an effective adaptive immune response. The chemokine CCL5 (RANTES) activates its cognate receptor, CCR5, to initiate cellular functions, including chemotaxis. In earlier studies, we reported that CCL5-induced CCR5 signaling activates the mTOR/4E-BP1 pathway to directly modulate mRNA translation. Specifically, CCL5-mediated mTOR activation contributes to T cell chemotaxis by initiating the synthesis of chemotaxis-related proteins. Up-regulation of chemotaxis-related proteins may prime T cells for efficient migration. It is now clear that mTOR is also a central regulator of nutrient sensing and glycolysis. Herein we describe a role for CCL5-mediated glucose uptake and ATP accumulation to meet the energy demands of chemotaxis in activated T cells. We provide evidence that CCL5 is able to induce glucose uptake in an mTOR-dependent manner. CCL5 treatment of ex vivo activated human CD3(+) T cells also induced the activation of the nutrient-sensing kinase AMPK and downstream substrates ACC-1, PFKFB-2, and GSK-3β. Using 2-deoxy-d-glucose, an inhibitor of glucose uptake, and compound C, an inhibitor of AMPK, experimental data are presented that demonstrate that CCL5-mediated T cell chemotaxis is dependent on glucose, as these inhibitors inhibit CCL5-mediated chemotaxis in a dose-dependent manner. Altogether, these findings suggest that both glycolysis and AMPK signaling are required for efficient T cell migration in response to CCL5. These studies extend the role of CCL5 mediated CCR5 signaling beyond lymphocyte chemotaxis and demonstrate a role for chemokines in promoting glucose uptake and ATP production to match energy demands of migration.
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Affiliation(s)
- Olivia Chan
- Toronto General Research Institute, University Health Network and Department of Immunology, University of Toronto, Toronto, Ontario M5G 2M1, Canada
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45
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Oliveira SM, Zhang YH, Solis RS, Isackson H, Bellahcene M, Yavari A, Pinter K, Davies JK, Ge Y, Ashrafian H, Walker JW, Carling D, Watkins H, Casadei B, Redwood C. AMP-activated protein kinase phosphorylates cardiac troponin I and alters contractility of murine ventricular myocytes. Circ Res 2012; 110:1192-201. [PMID: 22456184 DOI: 10.1161/circresaha.111.259952] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
RATIONALE AMP-activated protein kinase (AMPK) is an important regulator of energy balance and signaling in the heart. Mutations affecting the regulatory γ2 subunit have been shown to cause an essentially cardiac-restricted phenotype of hypertrophy and conduction disease, suggesting a specific role for this subunit in the heart. OBJECTIVE The γ isoforms are highly conserved at their C-termini but have unique N-terminal sequences, and we hypothesized that the N-terminus of γ2 may be involved in conferring substrate specificity or in determining intracellular localization. METHODS AND RESULTS A yeast 2-hybrid screen of a human heart cDNA library using the N-terminal 273 residues of γ2 as bait identified cardiac troponin I (cTnI) as a putative interactor. In vitro studies showed that cTnI is a good AMPK substrate and that Ser150 is the principal residue phosphorylated. Furthermore, on AMPK activation during ischemia, Ser150 is phosphorylated in whole hearts. Using phosphomimics, measurements of actomyosin ATPase in vitro and force generation in demembraneated trabeculae showed that modification at Ser150 resulted in increased Ca(2+) sensitivity of contractile regulation. Treatment of cardiomyocytes with the AMPK activator 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) resulted in increased myocyte contractility without changing the amplitude of Ca(2+) transient and prolonged relaxation despite shortening the time constant of Ca(2+) transient decay (tau). Compound C prevented the effect of AICAR on myocyte function. These results suggest that AMPK activation increases myocyte contraction and prolongs relaxation by increasing myofilament Ca(2+) sensitivity. CONCLUSIONS We conclude that cTnI phosphorylation by AMPK may represent a novel mechanism of regulation of cardiac function.
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46
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Andersen RO, Turnbull DW, Johnson EA, Doe CQ. Sgt1 acts via an LKB1/AMPK pathway to establish cortical polarity in larval neuroblasts. Dev Biol 2012; 363:258-65. [PMID: 22248825 DOI: 10.1016/j.ydbio.2011.12.047] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Revised: 11/25/2011] [Accepted: 12/30/2011] [Indexed: 10/14/2022]
Abstract
Drosophila neuroblasts are a model system for studying stem cell self-renewal and the establishment of cortical polarity. Larval neuroblasts generate a large apical self-renewing neuroblast, and a small basal cell that differentiates. We performed a genetic screen to identify regulators of neuroblast self-renewal, and identified a mutation in sgt1 (suppressor-of-G2-allele-of-skp1) that had fewer neuroblasts. We found that sgt1 neuroblasts have two polarity phenotypes: failure to establish apical cortical polarity at prophase, and lack of cortical Scribble localization throughout the cell cycle. Apical cortical polarity was partially restored at metaphase by a microtubule-induced cortical polarity pathway. Double mutants lacking Sgt1 and Pins (a microtubule-induced polarity pathway component) resulted in neuroblasts without detectable cortical polarity and formation of "neuroblast tumors." Mutants in hsp83 (encoding the predicted Sgt1-binding protein Hsp90), LKB1, or AMPKα all show similar prophase apical cortical polarity defects (but no Scribble phenotype), and activated AMPKα rescued the sgt1 mutant phenotype. We propose that an Sgt1/Hsp90-LKB1-AMPK pathway acts redundantly with a microtubule-induced polarity pathway to generate neuroblast cortical polarity, and the absence of neuroblast cortical polarity can produce neuroblast tumors.
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Affiliation(s)
- Ryan O Andersen
- Institute of Neuroscience, University of Oregon, Eugene, Oregon 97403, USA
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Wentzell JS, Bolkan BJ, Carmine-Simmen K, Swanson TL, Musashe DT, Kretzschmar D. Amyloid precursor proteins are protective in Drosophila models of progressive neurodegeneration. Neurobiol Dis 2012; 46:78-87. [PMID: 22266106 DOI: 10.1016/j.nbd.2011.12.047] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 12/06/2011] [Accepted: 12/31/2011] [Indexed: 12/11/2022] Open
Abstract
The processing of Amyloid Precursor Proteins (APPs) results in several fragments, including soluble N-terminal ectodomains (sAPPs) and C-terminal intracellular domains (AICD). sAPPs have been ascribed neurotrophic or neuroprotective functions in cell culture, although β-cleaved sAPPs can have deleterious effects and trigger neuronal cell death. Here we describe a neuroproprotective function of APP and fly APPL (Amyloid Precursor Protein-like) in vivo in several Drosophila mutants with progressive neurodegeneration. We show that expression of the N-terminal ectodomain is sufficient to suppress the progressive degeneration in these mutants and that the secretion of the ectodomain is required for this function. In addition, a protective effect is achieved by expressing kuzbanian (which has α-secretase activity) whereas expression of fly and human BACE aggravates the phenotypes, suggesting that the protective function is specifically mediated by the α-cleaved ectodomain. Furthermore, genetic and molecular studies suggest that the N-terminal fragments interact with full-length APPL activating a downstream signaling pathway via the AICD. Because we show protective effects in mutants that affect different genes (AMP-activated protein kinase, MAP1b, rasGAP), we propose that the protective effect is not due to a genetic interaction between APPL and these genes but a more general aspect of APP proteins. The result that APP proteins and specifically their soluble α-cleaved ectodomains can protect against progressive neurodegeneration in vivo provides support for the hypothesis that a disruption of the physiological function of APP could play a role in the pathogenesis of Alzheimer's Disease.
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Affiliation(s)
- Jill S Wentzell
- Center for Research on Occupational and Environmental Toxicology, Oregon Health & Sciences University, Portland, OR 97239, USA
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Scott KEN, Wheeler FB, Davis AL, Thomas MJ, Ntambi JM, Seals DF, Kridel SJ. Metabolic regulation of invadopodia and invasion by acetyl-CoA carboxylase 1 and de novo lipogenesis. PLoS One 2012; 7:e29761. [PMID: 22238651 PMCID: PMC3253107 DOI: 10.1371/journal.pone.0029761] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Accepted: 12/04/2011] [Indexed: 01/04/2023] Open
Abstract
Invadopodia are membrane protrusions that facilitate matrix degradation and cellular invasion. Although lipids have been implicated in several aspects of invadopodia formation, the contributions of de novo fatty acid synthesis and lipogenesis have not been defined. Inhibition of acetyl-CoA carboxylase 1 (ACC1), the committed step of fatty acid synthesis, reduced invadopodia formation in Src-transformed 3T3 (3T3-Src) cells, and also decreased the ability to degrade gelatin. Inhibition of fatty acid synthesis through AMP-activated kinase (AMPK) activation and ACC phosphorylation also decreased invadopodia incidence. The addition of exogenous 16∶0 and 18∶1 fatty acid, products of de novo fatty acid synthesis, restored invadopodia and gelatin degradation to cells with decreased ACC1 activity. Pharmacological inhibition of ACC also altered the phospholipid profile of 3T3-Src cells, with the majority of changes occurring in the phosphatidylcholine (PC) species. Exogenous supplementation with the most abundant PC species, 34∶1 PC, restored invadopodia incidence, the ability to degrade gelatin and the ability to invade through matrigel to cells deficient in ACC1 activity. On the other hand, 30∶0 PC did not restore invadopodia and 36∶2 PC only restored invadopodia incidence and gelatin degradation, but not cellular invasion through matrigel. Pharmacological inhibition of ACC also reduced the ability of MDA-MB-231 breast, Snb19 glioblastoma, and PC-3 prostate cancer cells to invade through matrigel. Invasion of PC-3 cells through matrigel was also restored by 34∶1 PC supplementation. Collectively, the data elucidate the novel metabolic regulation of invadopodia and the invasive process by de novo fatty acid synthesis and lipogenesis.
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Affiliation(s)
- Kristen E. N. Scott
- Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, North Carolina, United States of America
| | - Frances B. Wheeler
- Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, North Carolina, United States of America
| | - Amanda L. Davis
- Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, North Carolina, United States of America
| | - Michael J. Thomas
- Department of Biochemistry, Wake Forest School of Medicine, Winston Salem, North Carolina, United States of America
- Comprehensive Cancer Center, Wake Forest School of Medicine, Winston Salem, North Carolina, United States of America
| | - James M. Ntambi
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Darren F. Seals
- Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, North Carolina, United States of America
- Comprehensive Cancer Center, Wake Forest School of Medicine, Winston Salem, North Carolina, United States of America
| | - Steven J. Kridel
- Department of Cancer Biology, Wake Forest School of Medicine, Winston Salem, North Carolina, United States of America
- Comprehensive Cancer Center, Wake Forest School of Medicine, Winston Salem, North Carolina, United States of America
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Phosphorylation of VASP by AMPK alters actin binding and occurs at a novel site. Biochem Biophys Res Commun 2011; 414:215-9. [DOI: 10.1016/j.bbrc.2011.09.059] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Accepted: 09/13/2011] [Indexed: 10/17/2022]
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50
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Han Q, Zhang X, Xue R, Yang H, Zhou Y, Kong X, Zhao P, Li J, Yang J, Zhu Y, Guan Y. AMPK potentiates hypertonicity-induced apoptosis by suppressing NFκB/COX-2 in medullary interstitial cells. J Am Soc Nephrol 2011; 22:1897-911. [PMID: 21903993 DOI: 10.1681/asn.2010080822] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Cells residing in the hypertonic, hypoxic renal medulla depend on dynamic adaptation mechanisms to respond to changes in energy supply and demand. The serine/threonine kinase 5'-AMP protein kinase (AMPK) is a sensor of cellular energy status, but whether it contributes to the survival of cells in the renal medulla is unknown. Here, hypertonic conditions induced a decrease in AMPK phosphorylation within 12 hours in renal medullary interstitial cells (RMIC), followed by a gradual return to baseline levels. Activation of AMPK markedly increased hypertonicity-induced apoptosis of RMICs and suppressed both hypertonicity-induced NFκB nuclear translocation and cyclooxygenase-2 (COX-2) activation; overexpression of COX-2 significantly attenuated these effects. AMPK activation also markedly reduced generation of reactive oxygen species and nuclear expression of tonicity-responsive enhancer-binding protein, which prevented upregulation of osmoprotective genes. In vivo, pharmacologic activation of AMPK led to massive apoptosis of RMICs and renal dysfunction in the setting of water deprivation in mice. Taken together, these results identify a critical role for AMPK in the maintenance of RMIC viability and suggest that AMPK modulates the NFκB-COX-2 survival pathway in the renal medulla. Furthermore, this study raises safety concerns for the development of AMPK activators as anti-diabetic drugs, especially for patients prone to dehydration.
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Affiliation(s)
- Qifei Han
- Department of Physiology and Pathophysiology, Peking University Health Science Center, Beijing, China
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