1
|
Höllring K, Vurnek D, Gehrer S, Dudziak D, Hubert M, Smith AS. Morphology as indicator of adaptive changes of model tissues in osmotically and chemically changing environments. BIOMATERIALS ADVANCES 2023; 154:213635. [PMID: 37804683 DOI: 10.1016/j.bioadv.2023.213635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 08/23/2023] [Accepted: 09/19/2023] [Indexed: 10/09/2023]
Abstract
We investigate the formation and maintenance of the homeostatic state in the case of 2D epithelial tissues following an induction of hyperosmotic conditions, using media enriched with 80 to 320 mOsm of mannitol, NaCl, and urea. We characterise the changes in the tissue immediately after the osmotic shock, and follow it until the new homeostatic state is formed. We characterise changes in cooperative motility and proliferation pressure in the tissue upon treatment with the help of a theoretical model based on the delayed Fisher-Kolmogorov formalism, where the delay in density evolution is induced by the the finite time of the cell division. Finally we explore the adaptation of the homeostatic tissue to highly elevated osmotic conditions by evaluating the morphology and topology of cells after 20 days in incubation. We find that hyperosmotic environments together with changes in the extracellular matrix induce different mechanical states in viable tissues, where only some remain functional. The perspective is a relation between tissue topology and function, which could be explored beyond the scope of this manuscript. Experimental investigation of morphological effect of change of osmotic conditions on long-term tissue morphology and topology Effect of osmotic changes on transient tissue growth behaviour Analysis of recovery process of tissues post-osmotic-shock Toxicity limits of osmolytes in mid- to long-term tissue evolution Tissue adaptation to physiological changes in environment Long-term tissue stabilisation under altered osmotic conditions.
Collapse
Affiliation(s)
- Kevin Höllring
- PULS Group, Institute for Theoretical Physics, FAU Erlangen-Nürnberg, Cauerstraße 3, 91058 Erlangen, Germany
| | - Damir Vurnek
- PULS Group, Institute for Theoretical Physics, FAU Erlangen-Nürnberg, Cauerstraße 3, 91058 Erlangen, Germany; Laboratory of Dendritic Cell Biology, Department of Dermatology, FAU Erlangen-Nürnberg, University Hospital Erlangen, Erlangen 91052, Germany
| | - Simone Gehrer
- PULS Group, Institute for Theoretical Physics, FAU Erlangen-Nürnberg, Cauerstraße 3, 91058 Erlangen, Germany
| | - Diana Dudziak
- Laboratory of Dendritic Cell Biology, Department of Dermatology, FAU Erlangen-Nürnberg, University Hospital Erlangen, Erlangen 91052, Germany
| | - Maxime Hubert
- PULS Group, Institute for Theoretical Physics, FAU Erlangen-Nürnberg, Cauerstraße 3, 91058 Erlangen, Germany; Group of Computational Life Sciences, Department of Physical Chemistry, Ruer Bošković Institute, Bijenička 54, Zagreb 10000, Croatia
| | - Ana-Sunčana Smith
- PULS Group, Institute for Theoretical Physics, FAU Erlangen-Nürnberg, Cauerstraße 3, 91058 Erlangen, Germany; Group of Computational Life Sciences, Department of Physical Chemistry, Ruer Bošković Institute, Bijenička 54, Zagreb 10000, Croatia.
| |
Collapse
|
2
|
Khandwala CB, Sarkar P, Schmidt HB, Ma M, Kinnebrew M, Pusapati GV, Patel BB, Tillo D, Lebensohn AM, Rohatgi R. Direct ionic stress sensing and mitigation by the transcription factor NFAT5. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.23.559074. [PMID: 37886503 PMCID: PMC10602047 DOI: 10.1101/2023.09.23.559074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
Homeostatic control of intracellular ionic strength is essential for protein, organelle and genome function, yet mechanisms that sense and enable adaptation to ionic stress remain poorly understood in animals. We find that the transcription factor NFAT5 directly senses solution ionic strength using a C-terminal intrinsically disordered region. Both in intact cells and in a purified system, NFAT5 forms dynamic, reversible biomolecular condensates in response to increasing ionic strength. This self-associative property, conserved from insects to mammals, allows NFAT5 to accumulate in the nucleus and activate genes that restore cellular ion content. Mutations that reduce condensation or those that promote aggregation both reduce NFAT5 activity, highlighting the importance of optimally tuned associative interactions. Remarkably, human NFAT5 alone is sufficient to reconstitute a mammalian transcriptional response to ionic or hypertonic stress in yeast. Thus NFAT5 is both the sensor and effector of a cell-autonomous ionic stress response pathway in animal cells.
Collapse
Affiliation(s)
- Chandni B. Khandwala
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Parijat Sarkar
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - H. Broder Schmidt
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Mengxiao Ma
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Maia Kinnebrew
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Ganesh V. Pusapati
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Bhaven B. Patel
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Desiree Tillo
- Center for Cancer Research Genomics Core, National Cancer Institute, National Institutes of Health, NIH, Building 37, RM 2056B, Bethesda, MD, 20892, USA
| | - Andres M. Lebensohn
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, NIH, Building 37, RM 2056B, Bethesda, MD, 20892, USA
| | - Rajat Rohatgi
- Departments of Biochemistry and Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| |
Collapse
|
3
|
Yoo EJ, Oh KH, Piao H, Kang HJ, Jeong GW, Park H, Lee CJ, Ryu H, Yang SH, Kim MG, Kim DK, Park SH, Lim BJ, Lee SM, Park CY, Choi SY, Lee-Kwon W, Yang J, Kwon HM. Macrophage transcription factor TonEBP promotes systemic lupus erythematosus and kidney injury via damage-induced signaling pathways. Kidney Int 2023; 104:163-180. [PMID: 37088425 DOI: 10.1016/j.kint.2023.03.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 03/06/2023] [Accepted: 03/17/2023] [Indexed: 04/25/2023]
Abstract
Systemic lupus erythematosus (SLE) is an autoimmune disorder characterized by autoreactive B cells and dysregulation of many other types of immune cells including myeloid cells. Lupus nephritis (LN) is a common target organ manifestations of SLE. Tonicity-responsive enhancer-binding protein (TonEBP, also known as nuclear factor of activated T-cells 5 (NFAT5)), was initially identified as a central regulator of cellular responses to hypertonic stress and is a pleiotropic stress protein involved in a variety of immunometabolic diseases. To explore the role of TonEBP, we examined kidney biopsy samples from patients with LN. Kidney TonEBP expression was found to be elevated in these patients compared to control patients - in both kidney cells and infiltrating immune cells. Kidney TonEBP mRNA was elevated in LN and correlated with mRNAs encoding inflammatory cytokines and the degree of proteinuria. In a pristane-induced SLE model in mice, myeloid TonEBP deficiency blocked the development of SLE and LN. In macrophages, engagement of various toll-like receptors (TLRs) that respond to damage-associated molecular patterns induced TonEBP expression via stimulation of its promoter. Intracellular signaling downstream of the TLRs was dependent on TonEBP. Therefore, TonEBP can act as a transcriptional cofactor for NF-κB, and activated mTOR-IRF3/7 via protein-protein interactions. Additionally, TonEBP-deficient macrophages displayed elevated efferocytosis and animals with myeloid deficiency of TonEBP showed reduced Th1 and Th17 differentiation, consistent with macrophages defective in TLR signaling. Thus, our data show that myeloid TonEBP may be an attractive therapeutic target for SLE and LN.
Collapse
Affiliation(s)
- Eun Jin Yoo
- Department of Biological Sciences, UNIST, Ulsan, Republic of Korea
| | - Kook-Hwan Oh
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Honglin Piao
- Department of Internal Medicine, Yonsei University College of Medicine, Severance Hospital, Seoul, Republic of Korea; Department of Medicine, Graduate School, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hyun Je Kang
- Department of Biological Sciences, UNIST, Ulsan, Republic of Korea
| | - Gyu Won Jeong
- Department of Biological Sciences, UNIST, Ulsan, Republic of Korea
| | - Hyun Park
- Department of Biological Sciences, UNIST, Ulsan, Republic of Korea
| | - Chang Jun Lee
- Department of Biological Sciences, UNIST, Ulsan, Republic of Korea
| | - Hyunjin Ryu
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Seung Hee Yang
- Kidney Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Myung-Gyu Kim
- Department of Internal Medicine, Korea University Anam Hospital, Seoul, Republic of Korea
| | - Dong Ki Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Sung Ho Park
- Department of Biological Sciences, UNIST, Ulsan, Republic of Korea
| | - Beom Jin Lim
- Department of Pathology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Sang Min Lee
- Department of Biological Sciences, UNIST, Ulsan, Republic of Korea
| | - Chan Young Park
- Department of Biological Sciences, UNIST, Ulsan, Republic of Korea
| | - Soo Youn Choi
- Department of Biological Sciences, UNIST, Ulsan, Republic of Korea; Department of Biology, Jeju National University, Jeju, Republic of Korea
| | - Whaseon Lee-Kwon
- Department of Biological Sciences, UNIST, Ulsan, Republic of Korea
| | - Jaeseok Yang
- Department of Internal Medicine, Yonsei University College of Medicine, Severance Hospital, Seoul, Republic of Korea.
| | - Hyug Moo Kwon
- Department of Biological Sciences, UNIST, Ulsan, Republic of Korea.
| |
Collapse
|
4
|
Clemente-Olivo MP, Hernández-Quiles M, Sparrius R, van der Stoel MM, Janssen V, Habibe JJ, van den Burg J, Jongejan A, Alcaraz-Sobrevals P, van Es R, Vos H, Kalkhoven E, de Vries CJM. Early adipogenesis is repressed through the newly identified FHL2-NFAT5 signaling complex. Cell Signal 2023; 104:110587. [PMID: 36610523 DOI: 10.1016/j.cellsig.2023.110587] [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: 10/31/2022] [Revised: 12/25/2022] [Accepted: 01/03/2023] [Indexed: 01/06/2023]
Abstract
The LIM-domain-only protein FHL2 is a modulator of signal transduction and has been shown to direct the differentiation of mesenchymal stem cells towards osteoblast and myocyte phenotypes. We hypothesized that FHL2 may simultaneously interfere with the induction of the adipocyte lineage. Therefore, we investigated the role of FHL2 in adipocyte differentiation. For these studies pre-adipocytes isolated from mouse adipose tissue and the 3T3-L1 (pre)adipocyte cell line were applied. We performed FHL2 gain of function and knockdown experiments followed by extensive RNAseq analyses and phenotypic characterization of the cells by oil-red O (ORO) lipid staining. Through affinity-purification mass spectrometry (AP-MS) novel FHL2 interacting proteins were identified. Here we report that FHL2 is expressed in pre-adipocytes and for accurate adipocyte differentiation, this protein needs to be downregulated during the early stages of adipogenesis. More specifically, constitutive overexpression of FHL2 drastically inhibits adipocyte differentiation in 3T3-L1 cells, which was demonstrated by suppressed activation of the adipogenic gene expression program as shown by RNAseq analyses, and diminished lipid accumulation. Analysis of the protein-protein interactions mediating this repressive activity of FHL2 on adipogenesis revealed the interaction of FHL2 with the Nuclear factor of activated T-cells 5 (NFAT5). NFAT5 is an established inhibitor of adipocyte differentiation and its knockdown rescued the inhibitory effect of FHL2 overexpression on 3T3-L1 differentiation, indicating that these proteins act cooperatively. We present a new regulatory function of FHL2 in early adipocyte differentiation and revealed that FHL2-mediated inhibition of pre-adipocyte differentiation is dependent on its interaction with NFAT5. FHL2 expression increases with aging, which may affect mesenchymal stem cell differentiation, more specifically inhibit adipocyte differentiation.
Collapse
Affiliation(s)
- Maria P Clemente-Olivo
- Amsterdam UMC location University of Amsterdam, Department of Medical Biochemistry, Amsterdam, the Netherlands; Amsterdam Cardiovascular Sciences, and Amsterdam Gastroenterology, Endocrinology and Metabolism, University of Amsterdam, Amsterdam, the Netherlands
| | - Miguel Hernández-Quiles
- Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Rinske Sparrius
- Amsterdam UMC location University of Amsterdam, Department of Medical Biochemistry, Amsterdam, the Netherlands
| | - Miesje M van der Stoel
- Amsterdam UMC location University of Amsterdam, Department of Medical Biochemistry, Amsterdam, the Netherlands
| | - Vera Janssen
- Amsterdam UMC location University of Amsterdam, Department of Medical Biochemistry, Amsterdam, the Netherlands
| | - Jayron J Habibe
- Amsterdam UMC location University of Amsterdam, Department of Medical Biochemistry, Amsterdam, the Netherlands; Amsterdam Cardiovascular Sciences, and Amsterdam Gastroenterology, Endocrinology and Metabolism, University of Amsterdam, Amsterdam, the Netherlands
| | - Janny van den Burg
- Amsterdam UMC location University of Amsterdam, Department of Medical Biochemistry, Amsterdam, the Netherlands
| | - Aldo Jongejan
- Amsterdam UMC location University of Amsterdam, Department of Bioinformatics, Amsterdam, the Netherlands
| | - Paula Alcaraz-Sobrevals
- Oncode Institute and Molecular Cancer Research, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Robert van Es
- Oncode Institute and Molecular Cancer Research, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Harmjan Vos
- Oncode Institute and Molecular Cancer Research, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Eric Kalkhoven
- Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Carlie J M de Vries
- Amsterdam UMC location University of Amsterdam, Department of Medical Biochemistry, Amsterdam, the Netherlands; Amsterdam Cardiovascular Sciences, and Amsterdam Gastroenterology, Endocrinology and Metabolism, University of Amsterdam, Amsterdam, the Netherlands.
| |
Collapse
|
5
|
Du C, Xu H, Cao C, Cao J, Zhang Y, Zhang C, Qiao R, Ming W, Li Y, Ren H, Cui X, Luan Z, Guan Y, Zhang X. Neutral amino acid transporter SLC38A2 protects renal medulla from hyperosmolarity-induced ferroptosis. eLife 2023; 12:80647. [PMID: 36722887 PMCID: PMC9949798 DOI: 10.7554/elife.80647] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Accepted: 01/31/2023] [Indexed: 02/02/2023] Open
Abstract
Hyperosmolarity of the renal medulla is essential for urine concentration and water homeostasis. However, how renal medullary collecting duct (MCD) cells survive and function under harsh hyperosmotic stress remains unclear. Using RNA-Seq, we identified SLC38A2 as a novel osmoresponsive neutral amino acid transporter in MCD cells. Hyperosmotic stress-induced cell death in MCD cells occurred mainly via ferroptosis, and it was significantly attenuated by SLC38A2 overexpression but worsened by Slc38a2-gene deletion or silencing. Mechanistic studies revealed that the osmoprotective effect of SLC38A2 is dependent on the activation of mTORC1. Moreover, an in vivo study demonstrated that Slc38a2-knockout mice exhibited significantly increased medullary ferroptosis following water restriction. Collectively, these findings reveal that Slc38a2 is an important osmoresponsive gene in the renal medulla and provide novel insights into the critical role of SLC38A2 in protecting MCD cells from hyperosmolarity-induced ferroptosis via the mTORC1 signalling pathway.
Collapse
Affiliation(s)
- Chunxiu Du
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Dalian Medical UniversityDalianChina
- Dalian Key Laboratory for Nuclear Receptors in Major Metabolic DiseasesDalianChina
- Health Science Center, East China Normal UniversityShanghaiChina
| | - Hu Xu
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
| | - Cong Cao
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
| | - Jiahui Cao
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
| | - Yufei Zhang
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
| | - Cong Zhang
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
| | - Rongfang Qiao
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
| | - Wenhua Ming
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
| | - Yaqing Li
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
| | - Huiwen Ren
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
| | - Xiaohui Cui
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
| | - Zhilin Luan
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
| | - Youfei Guan
- Advanced Institute for Medical Sciences, Dalian Medical UniversityDalianChina
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Dalian Medical UniversityDalianChina
- Dalian Key Laboratory for Nuclear Receptors in Major Metabolic DiseasesDalianChina
| | - Xiaoyan Zhang
- Health Science Center, East China Normal UniversityShanghaiChina
| |
Collapse
|
6
|
Jimenez V, Miranda K, Ingrid A. The old and the new about the contractile vacuole of Trypanosoma cruzi. J Eukaryot Microbiol 2022; 69:e12939. [PMID: 35916682 PMCID: PMC11178379 DOI: 10.1111/jeu.12939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/27/2022] [Accepted: 07/27/2022] [Indexed: 11/28/2022]
Abstract
Osmoregulation is a conserved cellular process required for the survival of all organisms. In protists, the need for robust compensatory mechanisms that can maintain cell volume and tonicity within physiological range is even more relevant, as their life cycles are often completed in different environments. Trypanosoma cruzi, the protozoan pathogen responsible for Chagas disease, is transmitted by an insect vector to multiple types of mammalian hosts. The contractile vacuole complex (CVC) is an organelle that senses and compensates osmotic changes in the parasites, ensuring their survival upon ionic and osmotic challenges. Recent work shows that the contractile vacuole is also a key component of the secretory and endocytic pathways, regulating the selective targeting of surface proteins during differentiation. Here we summarize our current knowledge of the mechanisms involved in the osmoregulatory processes that take place in the vacuole, and we explore the new and exciting functions of this organelle in cell trafficking and signaling.
Collapse
Affiliation(s)
- Veronica Jimenez
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, California, USA
| | - Kildare Miranda
- Laboratorio de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Centro Nacional de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Augusto Ingrid
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, California, USA
- Laboratorio de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| |
Collapse
|
7
|
PARP1-mediated PARylation of TonEBP prevents R-loop-associated DNA damage. DNA Repair (Amst) 2021; 104:103132. [PMID: 34049076 DOI: 10.1016/j.dnarep.2021.103132] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 03/17/2021] [Accepted: 05/07/2021] [Indexed: 11/23/2022]
Abstract
Lack of coordination between the DNA replication and transcription machineries can increase the frequency of transcription-replication conflicts, leading ultimately to DNA damage and genomic instability. A major source of these conflicts is the formation of R-loops, which consist of a transcriptionally generated RNA-DNA hybrid and the displaced single-stranded DNA. R-loops play important physiological roles and have been implicated in human diseases. Although these structures have been extensively studied, many aspects of R-loop biology and R-loop-mediated genome instability remain unclear. We found that in cancer cells, tonicity-responsive enhancer-binding protein (TonEBP, also called NFAT5) interacted with PARP1 and localized to R-loops in response to DNA-damaging agent camptothecin (CPT), which is associated with R-loop formation. PARP1-mediated PARylation was required for recruitment of TonEBP to the sites of R-loop-associated DNA damage. Loss of TonEBP increased levels of R-loop accumulation and DNA damage, and promoted cell death in response to CPT. These findings suggest that TonEBP mediates resistance to CPT-induced cell death by preventing R-loop accumulation in cancer cells.
Collapse
|
8
|
Jobin K, Müller DN, Jantsch J, Kurts C. Sodium and its manifold impact on our immune system. Trends Immunol 2021; 42:469-479. [PMID: 33962888 DOI: 10.1016/j.it.2021.04.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 04/01/2021] [Accepted: 04/02/2021] [Indexed: 12/19/2022]
Abstract
The Western diet is rich in salt, and a high salt diet (HSD) is suspected to be a risk factor for cardiovascular diseases. It is now widely accepted that an experimental HSD can stimulate components of the immune system, potentially exacerbating certain autoimmune diseases, or alternatively, improving defenses against certain infections, such as cutaneous leishmaniasis. However, recent findings show that an experimental HSD may also aggravate other infections (e.g., pyelonephritis or systemic listeriosis). Here, we discuss the modulatory effects of a HSD on the microbiota, metabolic signaling, hormonal responses, local sodium concentrations, and their effects on various immune cell types in different tissues. We describe how these factors are integrated, resulting either in immune stimulation or suppression in various tissues and disease settings.
Collapse
Affiliation(s)
- Katarzyna Jobin
- Institute of Molecular Medicine and Experimental Immunology, University of Bonn, Bonn, Germany; Würzburg Institute of Systems Immunology, Max-Planck Research Group, University of Würzburg, Würzburg, Germany
| | - Dominik N Müller
- Experimental and Clinical Research Center (ECRC), a cooperation of Charité-Universitätsmedizin Berlin and Max Delbruck Center for Molecular Medicine, and Max Delbruck Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany; Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Jonathan Jantsch
- Institute of Clinical Microbiology and Hygiene, University Hospital of Regensburg and University of Regensburg, Regensburg, Germany.
| | - Christian Kurts
- Institute of Molecular Medicine and Experimental Immunology, University of Bonn, Bonn, Germany; Department of Microbiology and Immunology, Doherty Institute for Infection and Immunity, University of Melbourne, Victoria, Australia.
| |
Collapse
|
9
|
The PKA-p38MAPK-NFAT5-Organic Osmolytes Pathway in Duchenne Muscular Dystrophy: From Essential Player in Osmotic Homeostasis, Inflammation and Skeletal Muscle Regeneration to Therapeutic Target. Biomedicines 2021; 9:biomedicines9040350. [PMID: 33808305 PMCID: PMC8066813 DOI: 10.3390/biomedicines9040350] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/19/2021] [Accepted: 03/24/2021] [Indexed: 11/30/2022] Open
Abstract
In Duchenne muscular dystrophy (DMD), the absence of dystrophin from the dystrophin-associated protein complex (DAPC) causes muscle membrane instability, which leads to myofiber necrosis, hampered regeneration, and chronic inflammation. The resulting disabled DAPC-associated cellular pathways have been described both at the molecular and the therapeutical level, with the Toll-like receptor nuclear factor kappa-light-chain-enhancer of activated B cells pathway (NF-ƘB), Janus kinase/signal transducer and activator of transcription proteins, and the transforming growth factor-β pathways receiving the most attention. In this review, we specifically focus on the protein kinase A/ mitogen-activated protein kinase/nuclear factor of activated T-cells 5/organic osmolytes (PKA-p38MAPK-NFAT5-organic osmolytes) pathway. This pathway plays an important role in osmotic homeostasis essential to normal cell physiology via its regulation of the influx/efflux of organic osmolytes. Besides, NFAT5 plays an essential role in cell survival under hyperosmolar conditions, in skeletal muscle regeneration, and in tissue inflammation, closely interacting with the master regulator of inflammation NF-ƘB. We describe the involvement of the PKA-p38MAPK-NFAT5-organic osmolytes pathway in DMD pathophysiology and provide a clear overview of which therapeutic molecules could be of potential benefit to DMD patients. We conclude that modulation of the PKA-p38MAPK-NFAT5-organic osmolytes pathway could be developed as supportive treatment for DMD in conjunction with genetic therapy.
Collapse
|
10
|
Urso SJ, Lamitina T. The C. elegans Hypertonic Stress Response: Big Insights from Shrinking Worms. Cell Physiol Biochem 2021; 55:89-105. [PMID: 33626269 DOI: 10.33594/000000332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/08/2021] [Indexed: 12/23/2022] Open
Abstract
Cell volume is one of the most aggressively defended physiological set points in biology. Changes in intracellular ion and water concentrations, which are induced by changes in metabolism or environmental exposures, disrupt protein folding, enzymatic activity, and macromolecular assemblies. To counter these challenges, cells and organisms have evolved multifaceted, evolutionarily conserved molecular mechanisms to restore cell volume and repair stress induced damage. However, many unanswered questions remain regarding the nature of cell volume 'sensing' as well as the molecular signaling pathways involved in activating physiological response mechanisms. Unbiased genetic screening in the model organism C. elegans is providing new and unexpected insights into these questions, particularly questions relating to the hypertonic stress response (HTSR) pathway. One surprising characteristic of the HTSR pathway in C. elegans is that it is under strong negative regulation by proteins involved in protein homeostasis and the extracellular matrix (ECM). The role of the ECM in particular highlights the importance of studying the HTSR in the context of a live organism where native ECM-tissue associations are preserved. A second novel and recently discovered characteristic is that the HTSR is regulated at the post-transcriptional level. The goal of this review is to describe these discoveries, to provide context for their implications, and to raise outstanding questions to guide future research.
Collapse
Affiliation(s)
- Sarel J Urso
- University of Pittsburgh, Graduate Program in Cell Biology and Physiology, Pittsburgh, PA, USA.,University of Pittsburgh, Departments of Pediatrics and Cell Biology, Pittsburgh, PA, USA
| | - Todd Lamitina
- University of Pittsburgh, Graduate Program in Cell Biology and Physiology, Pittsburgh, PA, USA, .,University of Pittsburgh, Departments of Pediatrics and Cell Biology, Pittsburgh, PA, USA
| |
Collapse
|
11
|
Baumgartner L, Wuertz-Kozak K, Le Maitre CL, Wignall F, Richardson SM, Hoyland J, Ruiz Wills C, González Ballester MA, Neidlin M, Alexopoulos LG, Noailly J. Multiscale Regulation of the Intervertebral Disc: Achievements in Experimental, In Silico, and Regenerative Research. Int J Mol Sci 2021; 22:E703. [PMID: 33445782 PMCID: PMC7828304 DOI: 10.3390/ijms22020703] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/22/2020] [Accepted: 12/24/2020] [Indexed: 12/17/2022] Open
Abstract
Intervertebral disc (IVD) degeneration is a major risk factor of low back pain. It is defined by a progressive loss of the IVD structure and functionality, leading to severe impairments with restricted treatment options due to the highly demanding mechanical exposure of the IVD. Degenerative changes in the IVD usually increase with age but at an accelerated rate in some individuals. To understand the initiation and progression of this disease, it is crucial to identify key top-down and bottom-up regulations' processes, across the cell, tissue, and organ levels, in health and disease. Owing to unremitting investigation of experimental research, the comprehension of detailed cell signaling pathways and their effect on matrix turnover significantly rose. Likewise, in silico research substantially contributed to a holistic understanding of spatiotemporal effects and complex, multifactorial interactions within the IVD. Together with important achievements in the research of biomaterials, manifold promising approaches for regenerative treatment options were presented over the last years. This review provides an integrative analysis of the current knowledge about (1) the multiscale function and regulation of the IVD in health and disease, (2) the possible regenerative strategies, and (3) the in silico models that shall eventually support the development of advanced therapies.
Collapse
Affiliation(s)
- Laura Baumgartner
- BCN MedTech, Department of Information and Communication Technologies, Universitat Pompeu Fabra, 08018 Barcelona, Spain; (L.B.); (C.R.W.); (M.A.G.B.)
| | - Karin Wuertz-Kozak
- Department of Biomedical Engineering, Rochester Institute of Technology (RIT), Rochester, NY 14623, USA;
- Schön Clinic Munich Harlaching, Spine Center, Academic Teaching Hospital and Spine Research Institute of the Paracelsus Medical University Salzburg (Austria), 81547 Munich, Germany
| | - Christine L. Le Maitre
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield S1 1WB, UK;
| | - Francis Wignall
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Sciences Centre, Oxford Road, Manchester M13 9PT, UK; (F.W.); (S.M.R.); (J.H.)
| | - Stephen M. Richardson
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Sciences Centre, Oxford Road, Manchester M13 9PT, UK; (F.W.); (S.M.R.); (J.H.)
| | - Judith Hoyland
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Sciences Centre, Oxford Road, Manchester M13 9PT, UK; (F.W.); (S.M.R.); (J.H.)
| | - Carlos Ruiz Wills
- BCN MedTech, Department of Information and Communication Technologies, Universitat Pompeu Fabra, 08018 Barcelona, Spain; (L.B.); (C.R.W.); (M.A.G.B.)
| | - Miguel A. González Ballester
- BCN MedTech, Department of Information and Communication Technologies, Universitat Pompeu Fabra, 08018 Barcelona, Spain; (L.B.); (C.R.W.); (M.A.G.B.)
- Catalan Institution for Research and Advanced Studies (ICREA), Pg. Lluis Companys 23, 08010 Barcelona, Spain
| | - Michael Neidlin
- Department of Mechanical Engineering, National Technical University of Athens, 15780 Athens, Greece; (M.N.); (L.G.A.)
| | - Leonidas G. Alexopoulos
- Department of Mechanical Engineering, National Technical University of Athens, 15780 Athens, Greece; (M.N.); (L.G.A.)
| | - Jérôme Noailly
- BCN MedTech, Department of Information and Communication Technologies, Universitat Pompeu Fabra, 08018 Barcelona, Spain; (L.B.); (C.R.W.); (M.A.G.B.)
| |
Collapse
|
12
|
Zhang C, Wang Z, Feng Q, Chen WD, Wang YD. Farnesoid X receptor: a potential therapeutic target in multiple organs. Histol Histopathol 2021; 35:1403-1414. [PMID: 33393073 DOI: 10.14670/hh-18-301] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Farnesoid X receptor (FXR), a member of the nuclear receptor family, is a common receptor found in the intestine and liver, and helps to maintain systemic metabolic homeostasis through regulating bile acid, glucose, lipid metabolism, and energy homeostatsis. In addition, FXR regulates the functions of various organs, such as liver, intestine, kidney, breast, pancreas, cardiovascular system and brain. FXR also plays a key role in regulation of gut-microbiota through mediating the various signaling pathways. Accordingly, FXR has become an attractive therapeutic target in a variety of diseases. This review combines classical and recent research reports to introduce the basic information about FXR and its important roles in various organs of the body.
Collapse
Affiliation(s)
- Chao Zhang
- State Key Laboratory of Chemical Resource Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, PR China
| | - Zixuan Wang
- State Key Laboratory of Chemical Resource Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, PR China
| | - Qingqing Feng
- State Key Laboratory of Chemical Resource Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, PR China
| | - Wei-Dong Chen
- Key Laboratory of Molecular Pathology, School of Basic Medical Science, Inner Mongolia Medical University, Hohhot, Inner Mongolia, PR China.,Key Laboratory of Receptors-Mediated Gene Regulation and Drug Discovery, the People's Hospital of Hebi, School of Medicine, Henan University, Henan, PR China
| | - Yan-Dong Wang
- State Key Laboratory of Chemical Resource Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, PR China.
| |
Collapse
|
13
|
Liu QQ, Li CM, Fu LN, Wang HL, Tan J, Wang YQ, Sun DF, Gao QY, Chen YX, Fang JY. Enterotoxigenic Bacteroides fragilis induces the stemness in colorectal cancer via upregulating histone demethylase JMJD2B. Gut Microbes 2020; 12:1788900. [PMID: 32684087 PMCID: PMC7524313 DOI: 10.1080/19490976.2020.1788900] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The enrichment of Enterotoxigenic Bacteroides fragilis (ETBF) has been identified in CRC patients and associated with worse prognosis. Cancer stem cells (CSCs) play essential roles in CRC development. However, whether ETBF is involved in CSCs regulation is unknown. To clarify the role of ETBF in CSCs properties, we performed extreme limited dilution assays (ELDA) in nude mice injected with ETBF-treated or untreated CRC cells subcutaneously, tumor organoids culture in azoxymethane (AOM) mouse model after gavaging with or without ETBF, and cell sphere formation assay after incubating CRC cell lines with or without ETBF. The results indicated that ETBF increased the stemness of CRC cells in vivo and in vitro. Furthermore, ETBF enhanced the expression of core stemness transcription factors Nanog homeobox (NANOG) and sex determining region Y-box 2 (SOX2). Histone H3 Lysine 9 trimethylation (H3K9me3) is critical in regulating CSCs properties. As an epigenetic and transcriptional regulator, JmjC-domain containing histone demethylase 2B (JMJD2B) is essential for embryonic stem cell (ESC) transformation and H3K9me3 demethylation. Mechanistically, ETBF infection significantly upregulated JMJD2B levels in CRC cell lines and nude mice xenograft model. JMJD2B epigenetically upregulated NANOG expression via demethylating its promoter H3K9me3, to mediate ETBF-induced stemness of CRC cells. Subsequently, we found that the Toll-like receptor 4 (TLR4) pathway, activated by ETBF, contributed to the enhanced expression of JMJD2B via nuclear transcription factor nuclear factor of activated T cells 5 (NFAT5). Finally, in human CRC samples, the amount of ETBF positively correlated with nuclear NFAT5, JMJD2B, and NANOG expression levels. In summary, ETBF upregulated JMJD2B levels in a TLR4-NFAT5-dependent pathway, and played an important role in stemness regulation, which promoted colorectal carcinogenesis.
Collapse
Affiliation(s)
- Qian-Qian Liu
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Chun-Min Li
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Lin-Na Fu
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Hao-Lian Wang
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Juan Tan
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yun-Qian Wang
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Dan-Feng Sun
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Qin-Yan Gao
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China,Qin-Yan Gao Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Renji Hospital, School of Medicine, Shanghai Institute of Digestive Disease, Shanghai Jiao Tong University, Shanghai200001, China
| | - Ying-Xuan Chen
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China,CONTACT Xuan Chen
| | - Jing-Yuan Fang
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| |
Collapse
|
14
|
Urso SJ, Comly M, Hanover JA, Lamitina T. The O-GlcNAc transferase OGT is a conserved and essential regulator of the cellular and organismal response to hypertonic stress. PLoS Genet 2020; 16:e1008821. [PMID: 33006972 PMCID: PMC7556452 DOI: 10.1371/journal.pgen.1008821] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 10/14/2020] [Accepted: 08/25/2020] [Indexed: 12/12/2022] Open
Abstract
The conserved O-GlcNAc transferase OGT O-GlcNAcylates serine and threonine residues of intracellular proteins to regulate their function. OGT is required for viability in mammalian cells, but its specific roles in cellular physiology are poorly understood. Here we describe a conserved requirement for OGT in an essential aspect of cell physiology: the hypertonic stress response. Through a forward genetic screen in Caenorhabditis elegans, we discovered OGT is acutely required for osmoprotective protein expression and adaptation to hypertonic stress. Gene expression analysis shows that ogt-1 functions through a post-transcriptional mechanism. Human OGT partially rescues the C. elegans phenotypes, suggesting that the osmoregulatory functions of OGT are ancient. Intriguingly, expression of O-GlcNAcylation-deficient forms of human or worm OGT rescue the hypertonic stress response phenotype. However, expression of an OGT protein lacking the tetracopeptide repeat (TPR) domain does not rescue. Our findings are among the first to demonstrate a specific physiological role for OGT at the organismal level and demonstrate that OGT engages in important molecular functions outside of its well described roles in post-translational O-GlcNAcylation of intracellular proteins.
Collapse
Affiliation(s)
- Sarel J. Urso
- Graduate Program in Cell Biology and Molecular Physiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Marcella Comly
- Laboratory of Cellular and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institute of Health, Bethesda, MD, United States of America
| | - John A. Hanover
- Laboratory of Cellular and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institute of Health, Bethesda, MD, United States of America
| | - Todd Lamitina
- Graduate Program in Cell Biology and Molecular Physiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
- Division of Child Neurology, Department of Pediatrics, Children’s Hospital of Pittsburgh, Pittsburgh, PA, United States of America
| |
Collapse
|
15
|
Kang HJ, Yoo EJ, Lee HH, An SM, Park H, Lee-Kwon W, Choi SY, Kwon HM. TonEBP Promotes β-Cell Survival under ER Stress by Enhancing Autophagy. Cells 2020; 9:cells9091928. [PMID: 32825390 PMCID: PMC7563687 DOI: 10.3390/cells9091928] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 08/17/2020] [Accepted: 08/19/2020] [Indexed: 12/16/2022] Open
Abstract
The endoplasmic reticulum (ER) stress response and autophagy are important cellular responses that determine cell fate and whose dysregulation is implicated in the perturbation of homeostasis and diseases. Tonicity-responsive enhancer-binding protein (TonEBP, also called NFAT5) is a pleiotropic stress protein that mediates both protective and pathological cellular responses. Here, we examined the role of TonEBP in β-cell survival under ER stress. We found that TonEBP increases β-cell survival under ER stress by enhancing autophagy. The level of TonEBP protein increased under ER stress due to a reduction in its degradation via the ubiquitin–proteasome pathway. In response to ER stress, TonEBP increased autophagosome formations and suppressed the accumulation of protein aggregates and β-cell death. The Rel-homology domain of TonEBP interacted with FIP200, which is essential for the initiation of autophagy, and was required for autophagy and cell survival upon exposure to ER stress. Mice in which TonEBP was specifically deleted in pancreatic endocrine progenitor cells exhibited defective glucose homeostasis and a loss of islet mass. Taken together, these findings demonstrate that TonEBP protects against ER stress-induced β-cell death by enhancing autophagy.
Collapse
|
16
|
TonEBP in dendritic cells mediates pro-inflammatory maturation and Th1/Th17 responses. Cell Death Dis 2020; 11:421. [PMID: 32499518 PMCID: PMC7272407 DOI: 10.1038/s41419-020-2632-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 05/19/2020] [Accepted: 05/21/2020] [Indexed: 12/29/2022]
Abstract
Dendritic cells (DCs) are potent antigen-presenting cells that link the innate and adaptive immune responses; as such they play pivotal roles in initiation and progression of rheumatoid arthritis (RA). Here, we report that the tonicity-responsive enhancer-binding protein (TonEBP or NFAT5), a Rel family protein involved in the pathogenesis of autoimmune disease and inflammation, is required for maturation and function of DCs. Myeloid cell-specific TonEBP deletion reduces disease severity in a murine model of collagen-induced arthritis; it also inhibits maturation of DCs and differentiation of pathogenic Th1 and Th17 cells in vivo. Upon stimulation by TLR4, TonEBP promotes surface expression of major histocompatibility complex class II and co-stimulatory molecules via p38 mitogen-activated protein kinase. This is followed by DC-mediated differentiation of pro-inflammatory Th1 and Th17 cells. Taken together, these findings provide mechanistic basis for the pathogenic role of TonEBP in RA and possibly other autoimmune diseases.
Collapse
|
17
|
Dumas SJ, Meta E, Borri M, Goveia J, Rohlenova K, Conchinha NV, Falkenberg K, Teuwen LA, de Rooij L, Kalucka J, Chen R, Khan S, Taverna F, Lu W, Parys M, De Legher C, Vinckier S, Karakach TK, Schoonjans L, Lin L, Bolund L, Dewerchin M, Eelen G, Rabelink TJ, Li X, Luo Y, Carmeliet P. Single-Cell RNA Sequencing Reveals Renal Endothelium Heterogeneity and Metabolic Adaptation to Water Deprivation. J Am Soc Nephrol 2019; 31:118-138. [PMID: 31818909 DOI: 10.1681/asn.2019080832] [Citation(s) in RCA: 110] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 10/01/2019] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Renal endothelial cells from glomerular, cortical, and medullary kidney compartments are exposed to different microenvironmental conditions and support specific kidney processes. However, the heterogeneous phenotypes of these cells remain incompletely inventoried. Osmotic homeostasis is vitally important for regulating cell volume and function, and in mammals, osmotic equilibrium is regulated through the countercurrent system in the renal medulla, where water exchange through endothelium occurs against an osmotic pressure gradient. Dehydration exposes medullary renal endothelial cells to extreme hyperosmolarity, and how these cells adapt to and survive in this hypertonic milieu is unknown. METHODS We inventoried renal endothelial cell heterogeneity by single-cell RNA sequencing >40,000 mouse renal endothelial cells, and studied transcriptome changes during osmotic adaptation upon water deprivation. We validated our findings by immunostaining and functionally by targeting oxidative phosphorylation in a hyperosmolarity model in vitro and in dehydrated mice in vivo. RESULTS We identified 24 renal endothelial cell phenotypes (of which eight were novel), highlighting extensive heterogeneity of these cells between and within the cortex, glomeruli, and medulla. In response to dehydration and hypertonicity, medullary renal endothelial cells upregulated the expression of genes involved in the hypoxia response, glycolysis, and-surprisingly-oxidative phosphorylation. Endothelial cells increased oxygen consumption when exposed to hyperosmolarity, whereas blocking oxidative phosphorylation compromised endothelial cell viability during hyperosmotic stress and impaired urine concentration during dehydration. CONCLUSIONS This study provides a high-resolution atlas of the renal endothelium and highlights extensive renal endothelial cell phenotypic heterogeneity, as well as a previously unrecognized role of oxidative phosphorylation in the metabolic adaptation of medullary renal endothelial cells to water deprivation.
Collapse
Affiliation(s)
- Sébastien J Dumas
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Elda Meta
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Mila Borri
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Jermaine Goveia
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Katerina Rohlenova
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Nadine V Conchinha
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Kim Falkenberg
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Laure-Anne Teuwen
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Laura de Rooij
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Joanna Kalucka
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Rongyuan Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Shawez Khan
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Federico Taverna
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Weisi Lu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Magdalena Parys
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Carla De Legher
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Stefan Vinckier
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Tobias K Karakach
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Luc Schoonjans
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium.,State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Lin Lin
- Lars Bolund Institute of Regenerative Medicine, Beijing Genomics Institute (BGI)-Qingdao, BGI-Shenzhen, Qingdao, China.,Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Lars Bolund
- Lars Bolund Institute of Regenerative Medicine, Beijing Genomics Institute (BGI)-Qingdao, BGI-Shenzhen, Qingdao, China.,Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Mieke Dewerchin
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Guy Eelen
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Ton J Rabelink
- Division of Nephrology, Department of Internal Medicine, The Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Xuri Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, Guangdong, China;
| | - Yonglun Luo
- Lars Bolund Institute of Regenerative Medicine, Beijing Genomics Institute (BGI)-Qingdao, BGI-Shenzhen, Qingdao, China; .,Department of Biomedicine, Aarhus University, Aarhus, Denmark.,China National GeneBank, Beijing Genomics Institute (BGI)-Shenzhen, Shenzhen, China; and.,Qingdao-Europe Advanced Institute for Life Sciences, Beijing Genomics Institute (BGI)-Qingdao, Qingdao, China
| | - Peter Carmeliet
- Department of Oncology, Laboratory of Angiogenesis and Vascular Metabolism, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium; .,Laboratory of Angiogenesis and Vascular Metabolism, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium.,State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, Guangdong, China
| |
Collapse
|
18
|
TonEBP/NFAT5 promotes obesity and insulin resistance by epigenetic suppression of white adipose tissue beiging. Nat Commun 2019; 10:3536. [PMID: 31387996 PMCID: PMC6684655 DOI: 10.1038/s41467-019-11302-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 07/08/2019] [Indexed: 12/22/2022] Open
Abstract
Tonicity-responsive enhancer binding protein (TonEBP or NFAT5) is a regulator of cellular adaptation to hypertonicity, macrophage activation and T-cell development. Here we report that TonEBP is an epigenetic regulator of thermogenesis and obesity. In mouse subcutaneous adipocytes, TonEBP expression increases > 50-fold in response to high-fat diet (HFD) feeding. Mice with TonEBP haplo-deficiency or adipocyte-specific TonEBP deficiency are resistant to HFD-induced obesity and metabolic defects (hyperglycemia, hyperlipidemia, and hyperinsulinemia). They also display increased oxygen consumption, resistance to hypothermia, and beiging of subcutaneous fat tissues. TonEBP suppresses the promoter of β3-adrenoreceptor gene, a critical regulator of lipolysis and thermogenesis, in ex vivo and cultured adipocytes. This involves recruitment of DNMT1 DNA methylase and methylation of the promoter. In human subcutaneous adipocytes TonEBP expression displays a correlation with body mass index but an inverse correlation with β3-adrenoreceptor expression. Thus, TonEBP is an attractive therapeutic target for obesity, insulin resistance, and hyperlipidemia. Activation of thermogenic beige adipocytes within white adipose tissue increases energy expenditure. Here, the authors show that expression of TonEBP in adipocytes is increased when mice are fed a high fat diet and that it suppresses expression of beta3-adrenoreceptor.
Collapse
|
19
|
Lin W, Shi C, Wang W, Wu H, Yang C, Wang A, Shen X, Tian Y, Cao P, Yuan W. Osmolarity and calcium regulate connective tissue growth factor (CTGF/CCN2) expression in nucleus pulposus cells. Gene 2019; 704:15-24. [PMID: 30965128 DOI: 10.1016/j.gene.2019.04.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 03/26/2019] [Accepted: 04/05/2019] [Indexed: 10/27/2022]
Abstract
OBJECTIVE The objective of our study was to verify the hypothesis that the expression of connective tissue growth factor (CTGF/CCN2), a key molecule essential for the maintenance of nucleus pulposus (NP) matrix homeostasis, is regulated by osmolarity and intracellular calcium in NP cells. METHODS Gene and protein expression levels of CCN2 were assessed using quantitative real-time PCR and western blot. Transfections and dual luciferase assays were performed to measure the effect of hyperosmolarity, tonicity enhancer binding protein (TonEBP) and Ca2+-calcineurin (Cn)-NFAT signaling on CCN2 promoter activity. RESULTS Cultured in hyperosmotic media, there was a significant decrease in the levels of CCN2 promoter activity, gene and protein expression in NP cells. The JASPAR database was used to analyze the construction of human CCN2 promoter, we found conserved TonE and NFAT binding sites. We then investigated whether TonEBP controlled CCN2 expression. Forced expression of TonEBP in NP cells showed that TonEBP negatively regulated CCN2 promoter activity, while suppression of TonEBP induced CCN2 promoter activity and expression. We then examined if Ca2+-Cn-NFAT signaling participated in the regulation of CCN2 expression. Co-expression of CCN2 reporter with individual NFAT1-4 expression plasmids and/or calcineurin A/B constructs suggested this signaling pathway played a role in the regulation of CCN2expression in NP cells. CONCLUSIONS Results of these studies illustrated that the expression of CCN2 in NP cells was regulated by the NFAT family through a signaling pathway network involving both activator (Ca2+-Cn-NFAT signaling) and suppressor (Hyperosmolarity-TonEBP) molecules.
Collapse
Affiliation(s)
- Wenbo Lin
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
| | - Changgui Shi
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
| | - Weiheng Wang
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
| | - Huiqiao Wu
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
| | - Chen Yang
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China
| | - An Wang
- Department of Orthopaedics, Shanghai Armed Police Force Hospital, Shanghai 201103, China
| | - Xiaolong Shen
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China
| | - Ye Tian
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China
| | - Peng Cao
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
| | - Wen Yuan
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
| |
Collapse
|
20
|
Yoo EJ, Lee HH, Ye BJ, Lee JH, Lee CY, Kang HJ, Jeong GW, Park H, Lim SW, Lee-Kwon W, Kwon HM, Choi SY. TonEBP Suppresses the HO-1 Gene by Blocking Recruitment of Nrf2 to Its Promoter. Front Immunol 2019; 10:850. [PMID: 31057560 PMCID: PMC6482272 DOI: 10.3389/fimmu.2019.00850] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 04/02/2019] [Indexed: 01/08/2023] Open
Abstract
TonEBP is a key transcriptional activator in macrophages with an M1 phenotype. High expression of TonEBP is associated with many inflammatory diseases. Heme oxygenase-1 (HO-1), a stress-inducible protein, is induced by various oxidative and inflammatory signals, and its expression is regarded as an adaptive cellular response to inflammation and oxidative injury. Here, we show that TonEBP suppresses expression of HO-1 by blocking Nrf2 binding to the HO-1 promoter, thereby inducing polarization of macrophages to the M1 phenotype. Inhibition of HO-1 expression or activity significantly reduced the inhibitory responses on M1 phenotype and stimulatory effects on M2 phenotype by TonEBP knockdown. Additional experiments showed that HO-1 plays a role in the paracrine anti-inflammatory effects of TonEBP knockdown in macrophages. Identification of HO-1 as a downstream effector of TonEBP provides new possibilities for improved therapeutic approaches to inflammatory diseases.
Collapse
Affiliation(s)
- Eun Jin Yoo
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Hwan Hee Lee
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Byeong Jin Ye
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Jun Ho Lee
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Chae Young Lee
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Hyun Je Kang
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Gyu Won Jeong
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Hyun Park
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Sun Woo Lim
- Transplantation Research Center, Catholic University of Korea, Seoul, South Korea
| | - Whaseon Lee-Kwon
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Hyug Moo Kwon
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| | - Soo Youn Choi
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, South Korea
| |
Collapse
|
21
|
Herman BA, Ferguson KM, Fernandez JVB, Kauffman S, Spicher JT, King RJ, Halterman JA. NFAT5 is differentially expressed in Sprague-Dawley rat tissues in response to high salt and high fructose diets. Genet Mol Biol 2019; 42:452-464. [PMID: 30816906 PMCID: PMC6726159 DOI: 10.1590/1678-4685-gmb-2018-0120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 07/24/2018] [Indexed: 12/31/2022] Open
Abstract
Current diets contain an increasing amount of salt and high fructose corn syrup,
but it remains unclear as to how dietary salt and fructose affect organ function
at the molecular level. This study aimed to test the hypothesis that consumption
of high salt and fructose diets would increase tissue-specific expression of two
critical osmotically-regulated genes, nuclear factor of activated T-cells 5
(NFAT5) and aldose reductase (AR). Fifty
Sprague-Dawley rats were placed on a control, 4% NaCl, 8% NaCl, or 64% fructose
diet for eight weeks. Fourteen different tissue samples were harvested and
snap-frozen, followed by RNA purification, cDNA synthesis, and
NFAT5 and AR gene expression
quantification by real-time PCR.Our findings demonstrate that
NFAT5 and AR expression are up-regulated
in the kidney medulla, liver, brain, and adipose tissue following consumption of
a high salt diet. NFAT5 expression is also up-regulated in the
kidney cortex following consumption of a 64% fructose diet. These findings
highlight the kidney medulla, liver, brain, and adipose tissue as being
“salt-responsive” tissues and reveal that a high fructose diet can lead to
enhanced NFAT5 expression in the kidney cortex. Further
characterization of signaling mechanisms involved could help elucidate how these
diets affect organ function long term.
Collapse
Affiliation(s)
- Braden A Herman
- Department of Biology, Eastern Mennonite University, Harrisonburg, VA, USA
| | - Kaylee M Ferguson
- Department of Biology, Eastern Mennonite University, Harrisonburg, VA, USA
| | - Jared V B Fernandez
- Master's in Biomedicine Program, Eastern Mennonite University, Harrisonburg, VA, USA
| | - Samantha Kauffman
- Department of Biology, Eastern Mennonite University, Harrisonburg, VA, USA
| | - Jason T Spicher
- Department of Biology, Eastern Mennonite University, Harrisonburg, VA, USA
| | - Rachel J King
- Department of Biology, Eastern Mennonite University, Harrisonburg, VA, USA
| | - Julia A Halterman
- Department of Biology, Eastern Mennonite University, Harrisonburg, VA, USA.,Master's in Biomedicine Program, Eastern Mennonite University, Harrisonburg, VA, USA
| |
Collapse
|
22
|
Maeoka Y, Wu Y, Okamoto T, Kanemoto S, Guo XP, Saito A, Asada R, Matsuhisa K, Masaki T, Imaizumi K, Kaneko M. NFAT5 up-regulates expression of the kidney-specific ubiquitin ligase gene Rnf183 under hypertonic conditions in inner-medullary collecting duct cells. J Biol Chem 2018; 294:101-115. [PMID: 30413537 DOI: 10.1074/jbc.ra118.002896] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 11/07/2018] [Indexed: 01/05/2023] Open
Abstract
We previously reported that among the 37 RING finger protein (RNF) family members, RNF183 mRNA is specifically expressed in the kidney under normal conditions. However, the mechanism supporting its kidney-specific expression pattern remains unclear. In this study, we elucidated the mechanism of the transcriptional activation of murine Rnf183 in inner-medullary collecting duct cells. Experiments with anti-RNF183 antibody revealed that RNF183 is predominantly expressed in the renal medulla. Among the 37 RNF family members, Rnf183 mRNA expression was specifically increased in hypertonic conditions, a hallmark of the renal medulla. RNF183 up-regulation was consistent with the activation of nuclear factor of activated T cells 5 (NFAT5), a transcription factor essential for adaptation to hypertonic conditions. Accordingly, siRNA-mediated knockdown of NFAT5 down-regulated RNF183 expression. Furthermore, the -3,466 to -3,136-bp region upstream of the mouse Rnf183 promoter containing the NFAT5-binding motif is conserved among mammals. A luciferase-based reporter vector containing the NFAT5-binding site was activated in response to hypertonic stress, but was inhibited by a mutation at the NFAT5-binding site. ChIP assays revealed that the binding of NFAT5 to this DNA site is enhanced by hypertonic stress. Of note, siRNA-mediated RNF183 knockdown increased hypertonicity-induced caspase-3 activation and decreased viability of mIMCD-3 cells. These results indicate that (i) RNF183 is predominantly expressed in the normal renal medulla, (ii) NFAT5 stimulates transcriptional activation of Rnf183 by binding to its cognate binding motif in the Rnf183 promoter, and (iii) RNF183 protects renal medullary cells from hypertonicity-induced apoptosis.
Collapse
Affiliation(s)
- Yujiro Maeoka
- Department of Biochemistry, Institute of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan; Department of Nephrology, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Yan Wu
- Department of Biochemistry, Institute of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Takumi Okamoto
- Department of Biochemistry, Institute of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Soshi Kanemoto
- Department of Biochemistry, Institute of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan; Department of Functional Anatomy and Neuroscience, Asahikawa Medical University, 2-1-1-1 Midorigaoka-higashi, Asahikawa, Hokkaido 078-8510, Japan
| | - Xiao Peng Guo
- Department of Biochemistry, Institute of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Atsushi Saito
- Department of Stress Protein Processing, Institute of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Rie Asada
- Department of Biochemistry, Institute of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan; Department of Medicine, Division of Endocrinology, Metabolism, and Lipid Research, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Koji Matsuhisa
- Department of Stress Protein Processing, Institute of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Takao Masaki
- Department of Nephrology, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Kazunori Imaizumi
- Department of Biochemistry, Institute of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan.
| | - Masayuki Kaneko
- Department of Biochemistry, Institute of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan.
| |
Collapse
|
23
|
Farnesoid X receptor is essential for the survival of renal medullary collecting duct cells under hypertonic stress. Proc Natl Acad Sci U S A 2018; 115:5600-5605. [PMID: 29739889 DOI: 10.1073/pnas.1803945115] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hypertonicity in renal medulla is critical for the kidney to produce concentrated urine. Renal medullary cells have to survive high medullary osmolarity during antidiuresis. Previous study reported that farnesoid X receptor (FXR), a nuclear receptor transcription factor activated by endogenous bile acids, increases urine concentrating ability by up-regulating aquaporin 2 expression in medullary collecting duct cells (MCDs). However, whether FXR is also involved in the maintenance of cell survival of MCDs under dehydration condition and hypertonic stress remains largely unknown. In the present study, we demonstrate that 24-hours water restriction selectively up-regulated renal medullary expression of FXR with little MCD apoptosis in wild-type mice. In contrast, water deprivation caused a massive apoptosis of MCDs in both global FXR gene-deficient mice and collecting duct-specific FXR knockout mice. In vitro studies showed that hypertonicity significantly increased FXR and tonicity response enhancer binding protein (TonEBP) expression in mIMCD3 cell line and primary cultured MCDs. Activation and overexpression of FXR markedly increased cell viability and decreased cell apoptosis under hyperosmotic conditions. In addition, FXR can increase gene expression and nuclear translocation of TonEBP. We conclude that FXR protects MCDs from hypertonicity-induced cell injury very likely via increasing TonEBP expression and nuclear translocation. This study provides insights into the molecular mechanism by which FXR enhances urine concentration via maintaining cell viability of MCDs under hyperosmotic condition.
Collapse
|
24
|
A Damage Sensor Associated with the Cuticle Coordinates Three Core Environmental Stress Responses in Caenorhabditis elegans. Genetics 2018; 208:1467-1482. [PMID: 29487136 PMCID: PMC5887142 DOI: 10.1534/genetics.118.300827] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Accepted: 02/08/2018] [Indexed: 12/24/2022] Open
Abstract
Although extracellular matrices function as protective barriers to many types of environmental insult, their role in sensing stress and regulating adaptive gene induction responses has not been studied carefully... Extracellular matrix barriers and inducible cytoprotective genes form successive lines of defense against chemical and microbial environmental stressors. The barrier in nematodes is a collagenous extracellular matrix called the cuticle. In Caenorhabditis elegans, disruption of some cuticle collagen genes activates osmolyte and antimicrobial response genes. Physical damage to the epidermis also activates antimicrobial responses. Here, we assayed the effect of knocking down genes required for cuticle and epidermal integrity on diverse cellular stress responses. We found that disruption of specific bands of collagen, called annular furrows, coactivates detoxification, hyperosmotic, and antimicrobial response genes, but not other stress responses. Disruption of other cuticle structures and epidermal integrity does not have the same effect. Several transcription factors act downstream of furrow loss. SKN-1/Nrf and ELT-3/GATA are required for detoxification, SKN-1/Nrf is partially required for the osmolyte response, and STA-2/Stat and ELT-3/GATA for antimicrobial gene expression. Our results are consistent with a cuticle-associated damage sensor that coordinates detoxification, hyperosmotic, and antimicrobial responses through overlapping, but distinct, downstream signaling.
Collapse
|
25
|
Peña-Oyarzun D, Troncoso R, Kretschmar C, Hernando C, Budini M, Morselli E, Lavandero S, Criollo A. Hyperosmotic stress stimulates autophagy via polycystin-2. Oncotarget 2017; 8:55984-55997. [PMID: 28915568 PMCID: PMC5593539 DOI: 10.18632/oncotarget.18995] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 06/21/2017] [Indexed: 12/13/2022] Open
Abstract
Various intracellular mechanisms are activated in response to stress, leading to adaptation or death. Autophagy, an intracellular process that promotes lysosomal degradation of proteins, is an adaptive response to several types of stress. Osmotic stress occurs under both physiological and pathological conditions, provoking mechanical stress and activating various osmoadaptive mechanisms. Polycystin-2 (PC2), a membrane protein of the polycystin family, is a mechanical sensor capable of activating the cell signaling pathways required for cell adaptation and survival. Here we show that hyperosmotic stress provoked by treatment with hyperosmolar concentrations of sorbitol or mannitol induces autophagy in HeLa and HCT116 cell lines. In addition, we show that mTOR and AMPK, two stress sensor proteins involved modulating autophagy, are downregulated and upregulated, respectively, when cells are subjected to hyperosmotic stress. Finally, our findings show that PC2 is required to promote hyperosmotic stress-induced autophagy. Downregulation of PC2 prevents inhibition of hyperosmotic stress-induced mTOR pathway activation. In conclusion, our data provide new insight into the role of PC2 as a mechanosensor that modulates autophagy under hyperosmotic stress conditions.
Collapse
Affiliation(s)
- Daniel Peña-Oyarzun
- Advanced Center for Chronic Diseases, Facultad Ciencias Quimicas y Farmaceuticas & Facultad Medicina, Universidad de Chile, Santiago, Chile.,Center for Molecular Studies of the Cell, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Rodrigo Troncoso
- Advanced Center for Chronic Diseases, Facultad Ciencias Quimicas y Farmaceuticas & Facultad Medicina, Universidad de Chile, Santiago, Chile.,Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile, Santiago, Chile
| | - Catalina Kretschmar
- Advanced Center for Chronic Diseases, Facultad Ciencias Quimicas y Farmaceuticas & Facultad Medicina, Universidad de Chile, Santiago, Chile.,Instituto de Investigación en Ciencias Odontológicas, Facultad de Odontología, Universidad de Chile, Santiago, Chile
| | - Cecilia Hernando
- Advanced Center for Chronic Diseases, Facultad Ciencias Quimicas y Farmaceuticas & Facultad Medicina, Universidad de Chile, Santiago, Chile.,Instituto de Investigación en Ciencias Odontológicas, Facultad de Odontología, Universidad de Chile, Santiago, Chile
| | - Mauricio Budini
- Instituto de Investigación en Ciencias Odontológicas, Facultad de Odontología, Universidad de Chile, Santiago, Chile
| | - Eugenia Morselli
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Sergio Lavandero
- Advanced Center for Chronic Diseases, Facultad Ciencias Quimicas y Farmaceuticas & Facultad Medicina, Universidad de Chile, Santiago, Chile.,Center for Molecular Studies of the Cell, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Department of Internal Medicine (Cardiology Division), University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Alfredo Criollo
- Advanced Center for Chronic Diseases, Facultad Ciencias Quimicas y Farmaceuticas & Facultad Medicina, Universidad de Chile, Santiago, Chile.,Instituto de Investigación en Ciencias Odontológicas, Facultad de Odontología, Universidad de Chile, Santiago, Chile
| |
Collapse
|
26
|
Johnson ZI, Shapiro IM, Risbud MV. RNA Sequencing Reveals a Role of TonEBP Transcription Factor in Regulation of Pro-inflammatory Genes in Response to Hyperosmolarity in Healthy Nucleus Pulposus Cells: A HOMEOSTATIC RESPONSE? J Biol Chem 2016; 291:26686-26697. [PMID: 27875309 DOI: 10.1074/jbc.m116.757732] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 10/12/2016] [Indexed: 11/06/2022] Open
Abstract
Transcription factor tonicity-responsive enhancer-binding protein (TonEBP/NFAT5) is critical for osmo-adaptation and extracellular matrix homeostasis of nucleus pulposus (NP) cells in their hypertonic tissue niche. Recent studies implicate TonEBP signaling in inflammatory disease and rheumatoid arthritis pathogenesis. However, broader functions of TonEBP in the disc remain unknown. RNA sequencing was performed on NP cells with TonEBP knockdown under hypertonic conditions. 1140 TonEBP-dependent genes were identified and categorized using Ingenuity Pathway Analysis. Bioinformatic analysis showed enrichment of matrix homeostasis and cytokine/chemokine signaling pathways. C-C motif chemokine ligand 2 (CCL2), interleukin 6 (IL6), tumor necrosis factor (TNF), and nitric oxide synthase 2 (NOS2) were studied further. Knockdown experiments showed that TonEBP was necessary to maintain expression levels of these genes. Gain- and loss-of-function experiments and site-directed mutagenesis demonstrated that TonEBP binding to a specific site in the CCL2 promoter is required for hypertonic inducibility. Despite inhibition by dominant-negative TonEBP, IL6 and NOS2 promoters were not hypertonicity-inducible. Whole-disc response to hypertonicity was studied in an ex vivo organ culture model, using wild-type and haploinsufficient TonEBP mice. Pro-inflammatory targets were induced by hypertonicity in discs from wild-type but not TonEBP-haploinsufficient mice. Mechanistically, NF-κB activity increased with hypertonicity and was necessary for hypertonic induction of target genes IL6, TNF, and NOS2 but not CCL2 Although TonEBP maintains transcription of genes traditionally considered pro-inflammatory, it is important to note that some of these genes also serve anabolic and pro-survival roles. Therefore, in NP cells, this phenomenon may reflect a physiological adaptation to diurnal osmotic loading of the intervertebral disc.
Collapse
Affiliation(s)
- Zariel I Johnson
- Graduate Program in Cell and Developmental Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107
| | - Irving M Shapiro
- Graduate Program in Cell and Developmental Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107.,From the Department of Orthopaedic Surgery and
| | - Makarand V Risbud
- Graduate Program in Cell and Developmental Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107 .,From the Department of Orthopaedic Surgery and
| |
Collapse
|
27
|
Simkova D, Kharaishvili G, Slabakova E, Murray PG, Bouchal J. Glycoprotein asporin as a novel player in tumour microenvironment and cancer progression. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2016; 160:467-473. [PMID: 27605398 DOI: 10.5507/bp.2016.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 07/08/2016] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Small leucine rich proteoglycans (SLRPs), major non-collagen components of the extracellular matrix (ECM), have multiple biological roles with diverse effects. Asporin, a member of the SLRPs class I, competes with other molecules in binding to collagen and affects its mineralization. Its role in cancer is only now being elucidated. METHODS The PubMed online database was used to search relevant reviews and original articles. Furthermore, altered asporin expression was analysed in publicly available genome-wide expression data at the Gene Expression Omnibus database. RESULTS Polymorphisms in the N-terminal polyaspartate domain, which binds calcium, are associated with osteoarthritis and prostate cancer. Asporin also promotes the progression of scirrhous gastric cancer where it is required for coordinated invasion by cancer associated fibroblasts and cancer cells. Besides the enhanced expression of asporin observed in multiple cancer types, such as breast, prostate, gastric, pancreas and colon cancer, tumour suppressive effects of asporin were described in triple-negative breast cancer. We also discuss a number of factors modulating asporin expression in different cell types relevant for alterations toing the tumour microenvironment. CONCLUSION The apparent contradicting tumour promoting and suppressive effects of asporin require further investigation. Deciphering the role of asporin and other SLRPs in tumour-stroma interactions is needed for a better understanding of cancer progression and potentially also for novel tumour microenvironment based therapies.
Collapse
Affiliation(s)
- Dana Simkova
- Department of Clinical and Molecular Pathology and Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Gvantsa Kharaishvili
- Department of Clinical and Molecular Pathology and Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Eva Slabakova
- Department of Cytokinetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Brno, Czech Republic
| | - Paul G Murray
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Jan Bouchal
- Department of Clinical and Molecular Pathology and Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| |
Collapse
|
28
|
Abstract
TonEBP is a key transcriptional activator of M1 phenotype in macrophage, and its high expression is associated with many inflammatory diseases. During the progression of the inflammatory responses, the M1 to M2 phenotypic switch enables the dual role of macrophages in controlling the initiation and resolution of inflammation. Here we report that in human and mouse M1 macrophages TonEBP suppresses IL-10 expression and M2 phenotype. TonEBP knockdown promoted the transcription of the IL-10 gene by enhancing chromatin accessibility and Sp1 recruitment to its promoter. The enhanced expression of M2 genes by TonEBP knockdown was abrogated by antagonism of IL-10 by either neutralizing antibodies or siRNA-mediated silencing. In addition, pharmacological suppression of TonEBP leads to similar upregulation of IL-10 and M2 genes. Thus, TonEBP suppresses M2 phenotype via downregulation of the IL-10 in M1 macrophages.
Collapse
|
29
|
LPS-induced NFκB enhanceosome requires TonEBP/NFAT5 without DNA binding. Sci Rep 2016; 6:24921. [PMID: 27118681 PMCID: PMC4847014 DOI: 10.1038/srep24921] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 04/07/2016] [Indexed: 12/24/2022] Open
Abstract
NFκB is a central mediator of inflammation. Present inhibitors of NFκB are mostly based on inhibition of essential machinery such as proteasome and protein kinases, or activation of nuclear receptors; as such, they are of limited therapeutic use due to severe toxicity. Here we report an LPS-induced NFκB enhanceosome in which TonEBP is required for the recruitment of p300. Increased expression of TonEBP enhances the NFκB activity and reduced TonEBP expression lowers it. Recombinant TonEBP molecules incapable of recruiting p300 do not stimulate NFκB. Myeloid-specific deletion of TonEBP results in milder inflammation and sepsis. We discover that a natural small molecule cerulenin specifically disrupts the enhanceosome without affecting the activation of NFκB itself. Cerulenin suppresses the pro-inflammatory activation of macrophages and sepsis without detectable toxicity. Thus, the NFκB enhanceosome offers a promising target for useful anti-inflammatory agents.
Collapse
|
30
|
Abstract
High extracellular NaCl is known to change expression of numerous genes, many of which are regulated by the osmoprotective transcription factor nuclear factor of activated T cells-5 (NFAT5). In the present study we employed RNA-Seq to provide a comprehensive, unbiased account of genes regulated by high NaCl in mouse embryonic fibroblast cells (MEFs). To identify genes regulated by NFAT5 we compared wild-type MEFs (WT-MEFs) to MEFs in which mutation of the NFAT5 gene inhibits its transcriptional activity (Null-MEFs). In WT-MEFs adding NaCl to raise osmolality from 300 to 500 mosmol/kg for 24 h increases expression of 167 genes and reduces expression of 412. Raising osmolality through multiple passages (adapted cells) increases expression of 196 genes and reduces expression of 528. In Null-MEFs, after 24 h of high NaCl, expression of 217 genes increase and 428 decrease, while in adapted Null-MEFs 143 increase and 622 decrease. Fewer than 10% of genes are regulated in common between WT- and null-MEFs, indicating a profound difference in regulation of high-NaCl induced genes induced by NFAT5 compared with those induced in the absence of NFAT5. Based on our findings we suggest a mechanism for this phenomenon, which had previously been unexplained. The NFAT5 DNA-binding motif (osmotic response element) is overrepresented in the vicinity of genes that NFAT5 upregulates, but not genes that it downregulates. We used Gene Ontology and manual curation to determine the function of the genes targeted by NFAT5, revealing many novel consequences of NFAT5 transcriptional activity.
Collapse
Affiliation(s)
- Yuichiro Izumi
- Systems Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Wenjing Yang
- Systems Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Jun Zhu
- Systems Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Maurice B Burg
- Systems Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Joan D Ferraris
- Systems Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
| |
Collapse
|
31
|
TonEBP suppresses adipogenesis and insulin sensitivity by blocking epigenetic transition of PPARγ2. Sci Rep 2015; 5:10937. [PMID: 26042523 PMCID: PMC4455245 DOI: 10.1038/srep10937] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 05/11/2015] [Indexed: 01/14/2023] Open
Abstract
TonEBP is a key transcription factor in cellular adaptation to hypertonic stress, and also in macrophage activation. Since TonEBP is involved in inflammatory diseases such as rheumatoid arthritis and atherosclerosis, we asked whether TonEBP played a role in adipogenesis and insulin resistance. Here we report that TonEBP suppresses adipogenesis and insulin signaling by inhibiting expression of the key transcription factor PPARγ2. TonEBP binds to the PPARγ2 promoter and blocks the epigenetic transition of the locus which is required for the activation of the promoter. When TonEBP expression is reduced, the epigenetic transition and PPARγ2 expression are markedly increased leading to enhanced adipogenesis and insulin response while inflammation is reduced. Thus, TonEBP is an independent determinant of adipose insulin sensitivity and inflammation. TonEBP is an attractive therapeutic target for insulin resistance in lieu of PPARγ agonists.
Collapse
|
32
|
Abstract
Articular cartilage is a unique load-bearing connective tissue with a low intrinsic capacity for repair and regeneration. Its avascularity makes it relatively hypoxic and its unique extracellular matrix is enriched with cations, which increases the interstitial fluid osmolarity. Several physicochemical and biomechanical stimuli are reported to influence chondrocyte metabolism and may be utilized for regenerative medical approaches. In this review article, we summarize the most relevant stimuli and describe how ion channels may contribute to cartilage homeostasis, with special emphasis on intracellular signaling pathways. We specifically focus on the role of calcium signaling as an essential mechanotransduction component and highlight the role of phosphatase signaling in this context.
Collapse
Affiliation(s)
- Holger Jahr
- Department of Orthopaedic Surgery, University Hospital RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
- The D-BOARD European Consortium for Biomarker Discovery, Surrey, UK
| | - Csaba Matta
- The D-BOARD European Consortium for Biomarker Discovery, Surrey, UK
- Department of Veterinary Preclinical Sciences, School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Duke of Kent Building, Guildford, Surrey GU2 7XH UK
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98, Debrecen, 4032 Hungary
| | - Ali Mobasheri
- The D-BOARD European Consortium for Biomarker Discovery, Surrey, UK
- Department of Veterinary Preclinical Sciences, School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Duke of Kent Building, Guildford, Surrey GU2 7XH UK
- Arthritis Research UK Centre for Sport, Exercise and Osteoarthritis, Arthritis Research UK Pain Centre, Medical Research Council and Arthritis Research UK Centre for Musculoskeletal Ageing Research, University of Nottingham, Queen’s Medical Centre, Nottingham, NG7 2UH UK
- Center of Excellence in Genomic Medicine Research (CEGMR), King Fahd Medical Research Center (KFMRC), King AbdulAziz University, Jeddah, 21589 Kingdom of Saudi Arabia
| |
Collapse
|
33
|
Arnaldo FB, Villar VAM, Konkalmatt PR, Owens SA, Asico LD, Jones JE, Yang J, Lovett DL, Armando I, Jose PA, Concepcion GP. D1-like dopamine receptors downregulate Na+-K+-ATPase activity and increase cAMP production in the posterior gills of the blue crab Callinectes sapidus. Am J Physiol Regul Integr Comp Physiol 2014; 307:R634-42. [PMID: 25080496 DOI: 10.1152/ajpregu.00555.2013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Dopamine-mediated regulation of Na(+)-K(+)-ATPase activity in the posterior gills of some crustaceans has been reported to be involved in osmoregulation. The dopamine receptors of invertebrates are classified into three groups based on their structure and pharmacology: D1- and D2-like receptors and a distinct invertebrate receptor subtype (INDR). We tested the hypothesis that a D1-like receptor is expressed in the blue crab Callinectes sapidus and regulates Na(+)-K(+)-ATPase activity. RT-PCR, using degenerate primers, showed the presence of D1βR mRNA in the posterior gill. The blue crab posterior gills showed positive immunostaining for a dopamine D5 receptor (D5R or D1βR) antibody in the basolateral membrane and cytoplasm. Confocal microscopy showed colocalization of Na(+)-K(+)-ATPase and D1βR in the basolateral membrane. To determine the effect of D1-like receptor stimulation on Na(+)-K(+)-ATPase activity, intact crabs acclimated to low salinity for 6 days were given an intracardiac infusion of the D1-like receptor agonist fenoldopam, with or without the D1-like receptor antagonist SCH23390. Fenoldopam increased cAMP production twofold and decreased Na(+)-K(+)-ATPase activity by 50% in the posterior gills. This effect was blocked by coinfusion with SCH23390, which had no effect on Na(+)-K(+)-ATPase activity by itself. Fenoldopam minimally decreased D1βR protein expression (10%) but did not affect Na(+)-K(+)-ATPase α-subunit protein expression. This study shows the presence of functional D1βR in the posterior gills of euryhaline crabs chronically exposed to low salinity and highlights the evolutionarily conserved function of the dopamine receptors on sodium homeostasis.
Collapse
Affiliation(s)
- Francis B Arnaldo
- The Marine Science Institute, University of the Philippines, Diliman, Quezon City, Philippines; Department of Pediatrics, Georgetown University School of Medicine, Washington, District of Columbia
| | - Van Anthony M Villar
- Department of Pediatrics, Georgetown University School of Medicine, Washington, District of Columbia; Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Prasad R Konkalmatt
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Shaun A Owens
- Department of Pediatrics, Georgetown University School of Medicine, Washington, District of Columbia
| | - Laureano D Asico
- Department of Pediatrics, Georgetown University School of Medicine, Washington, District of Columbia; Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - John E Jones
- Department of Pediatrics, Georgetown University School of Medicine, Washington, District of Columbia; Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Jian Yang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Donald L Lovett
- Department of Biology, The College of New Jersey, Ewing, New Jersey; and
| | - Ines Armando
- Department of Pediatrics, Georgetown University School of Medicine, Washington, District of Columbia; Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Pedro A Jose
- Department of Pediatrics, Georgetown University School of Medicine, Washington, District of Columbia; Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland; Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Gisela P Concepcion
- The Marine Science Institute, University of the Philippines, Diliman, Quezon City, Philippines
| |
Collapse
|
34
|
Kim JA, Kwon MJ, Lee-Kwon W, Choi SY, Sanada S, Kwon HM. Modulation of TonEBP activity by SUMO modification in response to hypertonicity. Front Physiol 2014; 5:200. [PMID: 24994984 PMCID: PMC4063170 DOI: 10.3389/fphys.2014.00200] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 05/09/2014] [Indexed: 01/06/2023] Open
Abstract
TonEBP is a DNA binding transcriptional enhancer that enables cellular adaptation to hypertonic stress by promoting expression of specific genes. TonEBP expression is very high in the renal medulla because local hypertonicity stimulates its expression. Given the high level of expression, it is not well understood how TonEBP activity is modulated. Here we report that TonEBP is post-translationally modified by SUMO, i.e., sumoylated, in the renal medulla but not in other isotonic organs. The sumoylation is reproduced in cultured cells when switched to hypertonicity. Analyses of site-directed TonEBP mutants reveal that K556 and K603 are independently sumoylated in response to hypertonicity. DNA binding is required for the sumoylation. Functional analyses of non-sumoylated mutants and SUMO-conjugated constructs show that sumoylation inhibits TonEBP in a dose-dependent manner but independent of the site of SUMO conjugation. Sumoylation inhibits transactivation without affecting nuclear translocation or DNA binding. These data suggest that sumoylation modulates the activity of TonEBP in the hypertonic renal medulla to prevent excessive action of TonEBP.
Collapse
Affiliation(s)
- Jeong-Ah Kim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology Ulsan, South Korea ; Department of Medicine, University of Maryland Baltimore, MD, USA
| | - Mi Jin Kwon
- Department of Biological Sciences, Ulsan National Institute of Science and Technology Ulsan, South Korea
| | - Whaseon Lee-Kwon
- Department of Biological Sciences, Ulsan National Institute of Science and Technology Ulsan, South Korea
| | - Soo Youn Choi
- Department of Biological Sciences, Ulsan National Institute of Science and Technology Ulsan, South Korea
| | - Satoru Sanada
- Department of Biological Sciences, Ulsan National Institute of Science and Technology Ulsan, South Korea ; Department of Medicine, University of Maryland Baltimore, MD, USA
| | - Hyug Moo Kwon
- Department of Biological Sciences, Ulsan National Institute of Science and Technology Ulsan, South Korea ; Department of Medicine, University of Maryland Baltimore, MD, USA
| |
Collapse
|
35
|
Kempson SA, Zhou Y, Danbolt NC. The betaine/GABA transporter and betaine: roles in brain, kidney, and liver. Front Physiol 2014; 5:159. [PMID: 24795654 PMCID: PMC4006062 DOI: 10.3389/fphys.2014.00159] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 04/04/2014] [Indexed: 12/18/2022] Open
Abstract
The physiological roles of the betaine/GABA transporter (BGT1; slc6a12) are still being debated. BGT1 is a member of the solute carrier family 6 (the neurotransmitter, sodium symporter transporter family) and mediates cellular uptake of betaine and GABA in a sodium- and chloride-dependent process. Most of the studies of BGT1 concern its function and regulation in the kidney medulla where its role is best understood. The conditions here are hostile due to hyperosmolarity and significant concentrations of NH4Cl and urea. To withstand the hyperosmolarity, cells trigger osmotic adaptation, involving concentration of a transcriptional factor TonEBP/NFAT5 in the nucleus, and accumulate betaine and other osmolytes. Data from renal cells in culture, primarily MDCK, revealed that transcriptional regulation of BGT1 by TonEBP/NFAT5 is relatively slow. To allow more acute control of the abundance of BGT1 protein in the plasma membrane, there is also post-translation regulation of BGT1 protein trafficking which is dependent on intracellular calcium and ATP. Further, betaine may be important in liver metabolism as a methyl donor. In fact, in the mouse the liver is the organ with the highest content of BGT1. Hepatocytes express high levels of both BGT1 and the only enzyme that can metabolize betaine, namely betaine:homocysteine –S-methyltransferase (BHMT1). The BHMT1 enzyme removes a methyl group from betaine and transfers it to homocysteine, a potential risk factor for cardiovascular disease. Finally, BGT1 has been proposed to play a role in controlling brain excitability and thereby represents a target for anticonvulsive drug development. The latter hypothesis is controversial due to very low expression levels of BGT1 relative to other GABA transporters in brain, and also the primary location of BGT1 at the surface of the brain in the leptomeninges. These issues are discussed in detail.
Collapse
Affiliation(s)
- Stephen A Kempson
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine Indianapolis, IN, USA
| | - Yun Zhou
- Department of Anatomy, Centre of Molecular Biology and Neuroscience, Institute of Basic Medical Sciences, University of Oslo Oslo, Norway
| | - Niels C Danbolt
- Department of Anatomy, Centre of Molecular Biology and Neuroscience, Institute of Basic Medical Sciences, University of Oslo Oslo, Norway
| |
Collapse
|
36
|
Park J, Kim H, Park SY, Lim SW, Kim YS, Lee DH, Roh GS, Kim HJ, Kang SS, Cho GJ, Jeong BY, Kwon HM, Choi WS. Tonicity-responsive enhancer binding protein regulates the expression of aldose reductase and protein kinase C δ in a mouse model of diabetic retinopathy. Exp Eye Res 2014; 122:13-9. [PMID: 24631337 DOI: 10.1016/j.exer.2014.03.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 02/24/2014] [Accepted: 03/02/2014] [Indexed: 12/25/2022]
Abstract
Recent studies revealed that Tonicity-responsive enhancer binding protein (TonEBP) directly regulates the transcription of aldose reductase (AR), which catalyzes the first step of the polyol pathway of glucose metabolism. Activation of protein kinase C δ (PKCδ) is dependent on AR and it has been linked to diabetic complications. However, whether TonEBP affects expressions of AR and PKCδ in diabetic retinopathy was not clearly shown. In this study, we used TonEBP heterozygote mice to study the role of TonEBP in streptozotocin (STZ)-induced diabetic retinopathy. We performed immunofluorescence staining and found that retinal expressions of AR and PKCδ were significantly reduced in the heterozygotes compared to wild type littermates, particularly in ganglion cell layer. To examine further the effect of TonEBP reduction in retinal tissues, we performed intravitreal injection of TonEBP siRNA and confirmed the decrease in AR and PKCδ levels. In addition, we found that a proapoptotic factor, Bax level was reduced and a survival factor, Bcl2 level was increased after injection of TonEBP siRNA, indicating that TonEBP mediates apoptotic cell death. In parallel, TonEBP siRNA was applied to the in vitro human retinal pigment epithelial (ARPE-19) cells cultured in high glucose media. We have consistently found the decrease in AR and PKCδ levels and changes in apoptotic factors for survival. Together, these results clearly demonstrated that hyperglycemia-induced TonEBP plays a crucial role in increasing AR and PKCδ levels and leading to apoptotic death. Our findings suggest that TonEBP reduction is an effective therapeutic strategy for diabetic retinopathy.
Collapse
Affiliation(s)
- Jeongsook Park
- Department of Anatomy and Neurobiology, Institute of Health Science, Medical Research Center for Neural Dysfunction, Gyeongsang National University School of Medicine, Jinju, Gyeongnam, Republic of Korea; Department of Food & Nutrition, College of Natural Sciences, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea
| | - Hwajin Kim
- Department of Anatomy and Neurobiology, Institute of Health Science, Medical Research Center for Neural Dysfunction, Gyeongsang National University School of Medicine, Jinju, Gyeongnam, Republic of Korea
| | - So Yun Park
- Department of Anatomy and Neurobiology, Institute of Health Science, Medical Research Center for Neural Dysfunction, Gyeongsang National University School of Medicine, Jinju, Gyeongnam, Republic of Korea
| | - Sun Woo Lim
- Transplant Research Center, The of Catholic University of Korea, Seoul, Republic of Korea
| | - Yoon Sook Kim
- Department of Anatomy and Neurobiology, Institute of Health Science, Medical Research Center for Neural Dysfunction, Gyeongsang National University School of Medicine, Jinju, Gyeongnam, Republic of Korea
| | - Dong Hoon Lee
- Department of Anatomy and Neurobiology, Institute of Health Science, Medical Research Center for Neural Dysfunction, Gyeongsang National University School of Medicine, Jinju, Gyeongnam, Republic of Korea
| | - Gu Seob Roh
- Department of Anatomy and Neurobiology, Institute of Health Science, Medical Research Center for Neural Dysfunction, Gyeongsang National University School of Medicine, Jinju, Gyeongnam, Republic of Korea
| | - Hyun Joon Kim
- Department of Anatomy and Neurobiology, Institute of Health Science, Medical Research Center for Neural Dysfunction, Gyeongsang National University School of Medicine, Jinju, Gyeongnam, Republic of Korea
| | - Sang Soo Kang
- Department of Anatomy and Neurobiology, Institute of Health Science, Medical Research Center for Neural Dysfunction, Gyeongsang National University School of Medicine, Jinju, Gyeongnam, Republic of Korea
| | - Gyeong Jae Cho
- Department of Anatomy and Neurobiology, Institute of Health Science, Medical Research Center for Neural Dysfunction, Gyeongsang National University School of Medicine, Jinju, Gyeongnam, Republic of Korea
| | - Bo-Young Jeong
- Department of Food & Nutrition, College of Natural Sciences, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea
| | - H Moo Kwon
- School of Nano-Biotechnology and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Wan Sung Choi
- Department of Anatomy and Neurobiology, Institute of Health Science, Medical Research Center for Neural Dysfunction, Gyeongsang National University School of Medicine, Jinju, Gyeongnam, Republic of Korea.
| |
Collapse
|
37
|
Zheng S, Liu J, Han Q, Huang S, Su W, Fu J, Jia X, Du S, Zhou Y, Zhang X, Guan Y. Metformin induces renal medullary interstitial cell apoptosis in type 2 diabetic mice. J Diabetes 2014; 6:132-46. [PMID: 24405721 DOI: 10.1111/1753-0407.12105] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Revised: 10/20/2013] [Accepted: 10/28/2013] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVE Metformin is a first-line antidiabetic drug for type 2 diabetes (T2D) with a relatively good safety profile. Metformin activates AMP-activated protein kinase (AMPK), which is crucial in maintaining renal medullary function, with inappropriate AMPK activation facilitating renal medullary interstitial cells (RMICs) apoptosis under hypertonic challenge. The present study was to determine the effects of metformin on RMIC survival in both normal and T2D mice. METHODS Mice (C57BL/6, db/m, and db/db) were treated with 450 mg/kg metformin for 7 days and subjected to 24-h water restriction (=dehydration) before being killed. Cell apoptosis in the renal medulla was determined by the terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labeling (TUNEL) assay. Cultured RMIC were treated with 10 mmol/L metformin in the presence or absence of hypertonic stress. Cell viability was determined and the underlying mechanisms were investigated. RESULTS Metformin induced significant apoptosis of RMIC in dehydrated normal mice and both hydrated and dehydrated T2D mice. Hypertonicity increased ATP production and inhibited AMPK phosphorylation in RMIC, which was attenuated by metformin. Metformin augmented hypertonicity-induced apoptosis of RMIC, suppressed the nuclear factor-κB/cyclo-oxygenase-2 pathway, reduced reactive oxygen species production and inhibited transcriptional activation of tonicity-responsive enhancer binding protein (TonEBP) and its downstream osmoprotective gene expression. CONCLUSIONS Metformin treatment is associated with increased RMIC apoptosis in both normally hydrated and dehydrated T2D mice. The results confirm AMPK as a critical factor involved in the maintenance of RMIC viability in T2D and raise safety concerns for metformin and other AMPK-activating antidiabetic drugs in dehydrated diabetic patients.
Collapse
Affiliation(s)
- Senfeng Zheng
- Department of Physiology and Pathophysiology, Key Laboratory of Cardiovascular Science of the Ministry of Education, Peking University Health Science Center, Beijing, China
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Woo JE, Kwon MY, Chung SW, Woo JM. Expression of TonEBP by Hypertonic and Hyperosmolar Stress in RGC-5 Cells. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2014. [DOI: 10.3341/jkos.2014.55.8.1195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Jong Eun Woo
- Department of Ophthalmology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea
| | - Min Young Kwon
- School of Biological Sciences, College of Natural Science, University of Ulsan, Ulsan, Korea
| | - Su Wol Chung
- School of Biological Sciences, College of Natural Science, University of Ulsan, Ulsan, Korea
| | - Je Moon Woo
- Department of Ophthalmology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea
| |
Collapse
|
39
|
Choi SY, Lee-Kwon W, Lee HH, Lee JH, Sanada S, Kwon HM. Multiple cell death pathways are independently activated by lethal hypertonicity in renal epithelial cells. Am J Physiol Cell Physiol 2013; 305:C1011-20. [PMID: 23986196 DOI: 10.1152/ajpcell.00384.2012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
When hypertonicity is imposed with sufficient intensity and acuteness, cells die. Here we investigated the cellular pathways involved in death using a cell line derived from renal epithelium. We found that hypertonicity rapidly induced activation of an intrinsic cell death pathway-release of cytochrome c and activation of caspase-3 and caspase-9-and an extrinsic pathway-activation of caspase-8. Likewise, a lysosomal pathway of cell death characterized by partial lysosomal rupture and release of cathepsin B from lysosomes to the cytosol was also activated. Relationships among the pathways were examined using specific inhibitors. Caspase inhibitors did not affect cathepsin B release into the cytosol by hypertonicity. In addition, cathepsin B inhibitors and caspase inhibitors did not affect hypertonicity-induced cytochrome c release, suggesting that the three pathways were independently activated. Combined inhibition of caspases and cathepsin B conferred significantly more protection from hypertonicity-induced cell death than inhibition of caspase or cathepsin B alone, indicating that all the three pathways contributed to the hypertonicity-induced cell death. Similar pattern of sensitivity to the inhibitors was observed in two other cell lines derived from renal epithelia. We conclude that multiple cell death pathways are independently activated early in response to lethal hypertonic stress in renal epithelial cells.
Collapse
Affiliation(s)
- Soo Youn Choi
- Department of Biological Science, Ulsan National Institute of Science and Technology, Ulsan, Korea; and
| | | | | | | | | | | |
Collapse
|
40
|
Zhou X, Wang H, Burg MB, Ferraris JD. High NaCl-induced inhibition of PTG contributes to activation of NFAT5 through attenuation of the negative effect of SHP-1. Am J Physiol Renal Physiol 2013; 305:F362-9. [PMID: 23720348 DOI: 10.1152/ajprenal.00218.2013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Activation of the transcription factor NFAT5 by high NaCl involves changes in phosphorylation. By siRNA screening, we previously found that protein targeting to glycogen (PTG), a regulatory subunit of protein phosphatase1 (PP1), contributes to regulation of high NaCl-induced NFAT5 transcriptional activity. The present study addresses the mechanism involved. We find that high NaCl-induced inhibition of PTG elevates NFAT5 activity by increasing NFAT5 transactivating activity, protein abundance, and nuclear localization. PTG acts via a catalytic subunit PP1γ. PTG associates physically with PP1γ, and NaCl reduces both this association and remaining PTG-associated PP1γ activity. High NaCl-induced phosphorylation of p38, ERK, and SHP-1 contributes to activation of NFAT5. Knockdown of PTG does not affect phosphorylation of p38 or ERK. However, PTG and PP1γ bind to SHP-1, and knockdown of either PTG or PP1γ increases high NaCl-induced phosphorylation of SHP-1-S591, which inhibits SHP-1. Mutation of SHP-1-S591 to alanine, which cannot be phosphorylated, increases inhibition of NFAT5 by SHP-1. Thus high NaCl reduces the stimulatory effect of PTG and PP1γ on SHP-1, which in turn reduces the inhibitory effect of SHP-1 on NFAT5. Our findings add to the known functions of PTG, which was previously recognized only for its glycogenic activity.
Collapse
Affiliation(s)
- Xiaoming Zhou
- Department of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd., Bethesda, MD 20814, USA.
| | | | | | | |
Collapse
|
41
|
A Single Amino Acid Substitution in the Renal Betaine/GABA Transporter Prevents Trafficking to the Plasma Membrane. ACTA ACUST UNITED AC 2013. [DOI: 10.1155/2013/598321] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
One response to hypertonic stress in the renal medulla and MDCK cells is the upregulation of betaine transporter (BGT1) synthesis, followed by trafficking to the plasma membrane (PM) and an increase in betaine transport. Upregulation of BGT1 was enhanced by inhibitors of phosphatases PP1 and PP2A and was attenuated by inhibitors of protein kinase C, suggesting an important role for phosphorylation reactions. This was tested using mutants of BGT1 tagged with EGFP. The PM trafficking motifs of BGT1 reside near the C terminus, and truncation at lysine560 resulted in a protein that remained intracellular during hypertonic stress. This K560Δ mutant colocalized with endoplasmic reticulum (ER). Substitution of alanine at Thr40, a putative phosphorylation site, also prevented trafficking to the PM during hypertonic stress. Live-cell imaging showed that T40A was not retained in the ER and colocalized with markers for Golgi and endosomes. In contrast, substitution of aspartate or glutamate at Thr40, to mimic phosphorylation, restored normal trafficking to the PM. HEK293 cells transfected with K560Δ or T40A mutants had 10% of the GABA transport activity of native BGT1, but normal transport activity was restored in cells expressing T40E. Normal BGT1 trafficking likely requires phosphorylation at Thr40 in addition to C-terminal motifs.
Collapse
|
42
|
Kim YH, Kim DH, Hwang J, Kim HS, Lim GY, Ryoo ZY, Choi SU, Lee S. The inclusion of fetal bovine serum in gelatin/PCL electrospun scaffolds reduces short-term osmotic stress in HEK 293 cells caused by scaffold components. J Appl Polym Sci 2013. [DOI: 10.1002/app.39052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
43
|
Ueno M, Shen WJ, Patel S, Greenberg AS, Azhar S, Kraemer FB. Fat-specific protein 27 modulates nuclear factor of activated T cells 5 and the cellular response to stress. J Lipid Res 2012; 54:734-743. [PMID: 23233732 DOI: 10.1194/jlr.m033365] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Fat-specific protein 27 (FSP27), a member of the cell death-inducing DNA fragmentation factor α-like effector (Cide) family, is highly expressed in adipose tissues and is a lipid droplet (LD)-associated protein that induces the accumulation of LDs. Using a yeast two-hybrid system to examine potential interactions of FSP27 with other proteins, a direct interaction with the N-terminal region of nuclear factor of activated T cells 5 (NFAT5) was identified. NFAT5 is a transcription factor that induces osmoprotective and inflammatory genes after its translocation to the nucleus. The interaction between FSP27 and NFAT5 was confirmed by bimolecular fluorescence complementation and coimmunoprecipitation. Using immunocytochemistry, NFAT5 is detected in the cytoplasm and in the nucleus under isotonic conditions; however, overexpression of FSP27 inhibited the hypertonic-induced nuclear translocation of NFAT5. Consistent with the suppression of NFAT5 nuclear translocation, in cells transfected with a reporter construct containing the NFAT5 response element from the monocyte chemoattractant protein 1 (MCP1) promoter, FSP27 overexpression repressed hypertonic-induced luciferase activity and the expression of NFAT5 target genes. Knockdown of FSP27 in differentiated 3T3-L1 adipocytes increased the NFAT5-mediated rise in MCP1. These results suggest that FSP27 not only modulates LD homeostasis but also modulates the response to osmotic stress via a physical interaction with NFAT5 at the LD surface.
Collapse
Affiliation(s)
- Masami Ueno
- Veterans Administration Palo Alto Health Care System, Palo Alto, CA, USA
| | | | | | | | | | | |
Collapse
|
44
|
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: 186] [Impact Index Per Article: 15.5] [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.
Collapse
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
| |
Collapse
|
45
|
Burkewitz K, Choe KP, Lee ECH, Deonarine A, Strange K. Characterization of the proteostasis roles of glycerol accumulation, protein degradation and protein synthesis during osmotic stress in C. elegans. PLoS One 2012; 7:e34153. [PMID: 22470531 PMCID: PMC3314593 DOI: 10.1371/journal.pone.0034153] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Accepted: 02/23/2012] [Indexed: 11/18/2022] Open
Abstract
Exposure of C. elegans to hypertonic stress-induced water loss causes rapid and widespread cellular protein damage. Survival in hypertonic environments depends critically on the ability of worm cells to detect and degrade misfolded and aggregated proteins. Acclimation of C. elegans to mild hypertonic stress suppresses protein damage and increases survival under more extreme hypertonic conditions. Suppression of protein damage in acclimated worms could be due to 1) accumulation of the chemical chaperone glycerol, 2) upregulation of protein degradation activity, and/or 3) increases in molecular chaperoning capacity of the cell. Glycerol and other chemical chaperones are widely thought to protect proteins from hypertonicity-induced damage. However, protein damage is unaffected by gene mutations that inhibit glycerol accumulation or that cause dramatic constitutive elevation of glycerol levels. Pharmacological or RNAi inhibition of proteasome and lyosome function and measurements of cellular protein degradation activity demonstrated that upregulation of protein degradation mechanisms plays no role in acclimation. Thus, changes in molecular chaperone capacity must be responsible for suppressing protein damage in acclimated worms. Transcriptional changes in chaperone expression have not been detected in C. elegans exposed to hypertonic stress. However, acclimation to mild hypertonicity inhibits protein synthesis 50–70%, which is expected to increase chaperone availability for coping with damage to existing proteins. Consistent with this idea, we found that RNAi silencing of essential translational components or acute exposure to cycloheximide results in a 50–80% suppression of hypertonicity-induced aggregation of polyglutamine-YFP (Q35::YFP). Dietary changes that increase protein production also increase Q35::YFP aggregation 70–180%. Our results demonstrate directly for the first time that inhibition of protein translation protects extant proteins from damage brought about by an environmental stressor, demonstrate important differences in aging- versus stress-induced protein damage, and challenge the widely held view that chemical chaperones are accumulated during hypertonic stress to protect protein structure/function.
Collapse
Affiliation(s)
- Kristopher Burkewitz
- Boylan Center for Cellular and Molecular Physiology, Mount Desert Island Biological Laboratory, Salisbury Cove, Maine, United States of America
| | | | | | | | | |
Collapse
|
46
|
Ortells MC, Morancho B, Drews-Elger K, Viollet B, Laderoute KR, López-Rodríguez C, Aramburu J. Transcriptional regulation of gene expression during osmotic stress responses by the mammalian target of rapamycin. Nucleic Acids Res 2012; 40:4368-84. [PMID: 22287635 PMCID: PMC3378878 DOI: 10.1093/nar/gks038] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Although stress can suppress growth and proliferation, cells can induce adaptive responses that allow them to maintain these functions under stress. While numerous studies have focused on the inhibitory effects of stress on cell growth, less is known on how growth-promoting pathways influence stress responses. We have approached this question by analyzing the effect of mammalian target of rapamycin (mTOR), a central growth controller, on the osmotic stress response. Our results showed that mammalian cells exposed to moderate hypertonicity maintained active mTOR, which was required to sustain their cell size and proliferative capacity. Moreover, mTOR regulated the induction of diverse osmostress response genes, including targets of the tonicity-responsive transcription factor NFAT5 as well as NFAT5-independent genes. Genes sensitive to mTOR-included regulators of stress responses, growth and proliferation. Among them, we identified REDD1 and REDD2, which had been previously characterized as mTOR inhibitors in other stress contexts. We observed that mTOR facilitated transcription-permissive conditions for several osmoresponsive genes by enhancing histone H4 acetylation and the recruitment of RNA polymerase II. Altogether, these results reveal a previously unappreciated role of mTOR in regulating transcriptional mechanisms that control gene expression during cellular stress responses.
Collapse
Affiliation(s)
- M Carmen Ortells
- Department of Experimental and Health Sciences, Universitat Pompeu Fabra, 08003 Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
47
|
Halterman JA, Kwon HM, Wamhoff BR. Tonicity-independent regulation of the osmosensitive transcription factor TonEBP (NFAT5). Am J Physiol Cell Physiol 2011; 302:C1-8. [PMID: 21998140 DOI: 10.1152/ajpcell.00327.2011] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Tonicity-responsive enhancer binding protein (TonEBP/nuclear factor of activated T-cells 5 [NFAT5]) is a Rel homology transcription factor classically known for its osmosensitive role in regulating cellular homeostasis during states of hypo- and hypertonic stress. A recently growing body of research indicates that TonEBP is not solely regulated by tonicity, but that it can be stimulated by various tonicity-independent mechanisms in both hypertonic and isotonic tissues. Physiological and pathophysiological stimuli such as cytokines, growth factors, receptor and integrin activation, contractile agonists, ions, and reactive oxygen species have been implicated in the positive regulation of TonEBP expression and activity in diverse cell types. These new data demonstrate that tonicity-independent stimulation of TonEBP is critical for tissue-specific functions like enhanced cell survival, migration, proliferation, vascular remodeling, carcinoma invasion, and angiogenesis. Continuing research will provide a better understanding as to how these and other alternative TonEBP stimuli regulate gene expression in both health and disease.
Collapse
Affiliation(s)
- Julia A Halterman
- Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA
| | | | | |
Collapse
|