1
|
Ma NS, Mumm S, Takahashi S, Levine MA. Multicentric Carpotarsal Osteolysis: a Contemporary Perspective on the Unique Skeletal Phenotype. Curr Osteoporos Rep 2023; 21:85-94. [PMID: 36477366 PMCID: PMC10393442 DOI: 10.1007/s11914-022-00762-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/18/2022] [Indexed: 12/12/2022]
Abstract
PURPOSE OF REVIEW Multicentric carpotarsal osteolysis (MCTO) is an ultra-rare disorder characterized by osteolysis of the carpal and tarsal bones, subtle craniofacial deformities, and nephropathy. The molecular pathways underlying the pathophysiology are not well understood. RECENT FINDINGS MCTO is caused by heterozygous mutations in MAFB, which encodes the widely expressed transcription factor MafB. All MAFB mutations in patients with MCTO result in replacement of amino acids that cluster in a phosphorylation region of the MafB transactivation domain and account for a presumed gain-of-function for the variant protein. Since 2012, fewer than 60 patients with MCTO have been described with 20 missense mutations in MAFB. The clinical presentations are variable, and a genotype-phenotype correlation is lacking. Osteolysis, via excessive osteoclast activity, has been regarded as the primary mechanism, although anti-resorptive agents demonstrate little therapeutic benefit. This paper appraises current perspectives of MafB protein action, inflammation, and dysfunctional bone formation on the pathogenesis of the skeletal phenotype in MCTO. More research is needed to understand the pathogenesis of MCTO to develop rational therapies.
Collapse
Affiliation(s)
- Nina S Ma
- Section of Pediatric Endocrinology, Children's Hospital Colorado and Department of Pediatrics, University of Colorado School of Medicine, 13123 E. 16th Ave, B265, Aurora, CO, 80045, USA.
| | - S Mumm
- Division of Bone and Mineral Diseases, Washington University School of Medicine and Center for Metabolic Bone Disease and Molecular Research, Shriners Children's, St. Louis, MO, USA
| | - S Takahashi
- Laboratory Animal Resource Center in Transborder Medical Research Center, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan
| | - M A Levine
- Center for Bone Health and Division of Endocrinology and Diabetes, The Children's Hospital of Philadelphia and the Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| |
Collapse
|
2
|
Saiga H, Ueno M, Tanaka T, Kaisho T, Hoshino K. Transcription factor MafB-mediated inhibition of type I interferons in plasmacytoid dendritic cells. Int Immunol 2021; 34:159-172. [PMID: 34734243 DOI: 10.1093/intimm/dxab103] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 11/01/2021] [Indexed: 11/14/2022] Open
Abstract
Type I IFNs (IFN-α and IFN-β), immunomodulatory cytokines secreted from activated plasmacytoid dendritic cells (pDCs), contribute to the innate defense against pathogenic infections and the pathogenesis of the autoimmune disease psoriasis vulgaris. A previous study has shown that an E26 transformation-specific (Ets) family transcription factor Spi-B can transactivate the type I IFN promoter in synergy with IFN regulatory factor (IRF)-7 and is required for type I IFN production in pDCs. However, the mechanism of negative regulation of type I IFNs by pDCs remains unknown. In this study, we report that a basic leucine zipper (bZip) transcription factor v-maf musculoaponeurotic fibrosarcoma oncogene homolog B (MafB) suppresses the induction of type I IFNs in pDCs. The elevated expression of MafB inhibited the transactivation of type I IFN genes in a dose-dependent manner. At the molecular level, MafB interacted with the Ets domain of Spi-B and interfered with IRF-7-Spi-B complexation. Decreased MafB mRNA expression and degradation of MafB protein in the early phase of immune responses led to the enhancement of type I IFNs in pDCs. In vivo studies indicated that MafB is involved in resistance against imiquimod-induced psoriasis-like skin inflammation. Overall, these findings demonstrate that MafB acts as a negative regulator of type I IFN induction in pDCs and plays an important role in maintaining immune homeostasis.
Collapse
Affiliation(s)
- Hiroyuki Saiga
- Department of Immunology, Faculty of Medicine, Kagawa University, Miki, Kagawa 761-0793, Japan
| | - Masaki Ueno
- Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Miki, Kagawa 761-0793, Japan
| | - Takashi Tanaka
- Laboratory for Inflammatory Regulation, RIKEN Center for Integrative Medical Science (IMS-RCAI), Yokohama, Kanagawa 230-0045, Japan
| | - Tsuneyasu Kaisho
- Laboratory for Inflammatory Regulation, RIKEN Center for Integrative Medical Science (IMS-RCAI), Yokohama, Kanagawa 230-0045, Japan.,Department of Immunology, Institute of Advanced Medicine, Wakayama Medical University, Kimiidera, Wakayama 641-8509, Japan
| | - Katsuaki Hoshino
- Department of Immunology, Faculty of Medicine, Kagawa University, Miki, Kagawa 761-0793, Japan.,Laboratory for Inflammatory Regulation, RIKEN Center for Integrative Medical Science (IMS-RCAI), Yokohama, Kanagawa 230-0045, Japan
| |
Collapse
|
3
|
Liang W, Yamahara K, Hernando-Erhard C, Lagies S, Wanner N, Liang H, Schell C, Kammerer B, Huber TB, Bork T. A reciprocal regulation of spermidine and autophagy in podocytes maintains the filtration barrier. Kidney Int 2020; 98:1434-1448. [PMID: 32603735 DOI: 10.1016/j.kint.2020.06.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 05/07/2020] [Accepted: 06/04/2020] [Indexed: 12/11/2022]
Abstract
Podocyte maintenance and stress resistance are exquisitely based on high basal rates of autophagy making these cells a unique model to unravel mechanisms of autophagy regulation. Polyamines have key cellular functions such as proliferation, nucleic acid biosynthesis and autophagy. Here we test whether endogenous spermidine signaling is a driver of basal and dynamic autophagy in podocytes by using genetic and pharmacologic approaches to interfere with different steps of polyamine metabolism. Translational studies revealed altered spermidine signaling in focal segmental glomerulosclerosis in vivo and in vitro. Exogenous spermidine supplementation emerged as new treatment strategy by successfully activating autophagy in vivo via inhibition of EP300, a protein with an essential role in controlling cell growth, cell division and prompting cells to differentiate to take on specialized functions. Surprisingly, gas chromatography-mass spectroscopy based untargeted metabolomics of wild type and autophagy deficient primary podocytes revealed a positive feedback mechanism whereby autophagy itself maintains polyamine metabolism and spermidine synthesis. The transcription factor MAFB acted as an upstream regulator of polyamine metabolism. Thus, our data highlight a novel positive feedback loop of autophagy and spermidine signaling allowing maintenance of high basal levels of autophagy as a key mechanism to sustain the filtration barrier. Hence, spermidine supplementation may emerge as a new therapeutic to restore autophagy in glomerular disease.
Collapse
Affiliation(s)
- Wei Liang
- Department of Medicine IV, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Division of Nephrology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Kosuke Yamahara
- Department of Medicine IV, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Camila Hernando-Erhard
- Department of Medicine IV, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Simon Lagies
- Center for Biological Systems Analysis, University of Freiburg, Freiburg, Germany; Spemann Graduate School of Biology and Medicine, University of Freiburg, Germany; Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Nicola Wanner
- III Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Huan Liang
- Department of Medicine IV, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Christoph Schell
- Department of Medicine IV, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Institute of Surgical Pathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Bernd Kammerer
- Center for Biological Systems Analysis, University of Freiburg, Freiburg, Germany; BIOSS Centre of Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Tobias B Huber
- III Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| | - Tillmann Bork
- Department of Medicine IV, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| |
Collapse
|
4
|
Tozaki-Saitoh H, Masuda J, Kawada R, Kojima C, Yoneda S, Masuda T, Inoue K, Tsuda M. Transcription factor MafB contributes to the activation of spinal microglia underlying neuropathic pain development. Glia 2018; 67:729-740. [PMID: 30485546 DOI: 10.1002/glia.23570] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 09/27/2018] [Accepted: 10/25/2018] [Indexed: 11/07/2022]
Abstract
Microglia, which are pathological effectors and amplifiers in the central nervous system, undergo various forms of activation. A well-studied microglial-induced pathological paradigm, spinal microglial activation following peripheral nerve injury (PNI), is a key event for the development of neuropathic pain but the transcription factors contributing to microglial activation are less understood. Herein, we demonstrate that MafB, a dominant transcriptional regulator of mature microglia, is involved in the pathology of a mouse model of neuropathic pain. PNI caused a rapid and marked increase of MafB expression selectively in spinal microglia but not in neurons. We also found that the microRNA mir-152 in the spinal cord which targets MafB expression decreased after PNI, and intrathecal administration of mir-152 mimic suppressed the development of neuropathic pain. Reduced MafB expression using heterozygous Mafb deficient mice and by intrathecal administration of siRNA alleviated the development of PNI-induced mechanical hypersensitivity. Furthermore, we found that intrathecal transfer of Mafb deficient microglia did not induce mechanical hypersensitivity and that conditional Mafb knockout mice did not develop neuropathic pain after PNI. We propose that MafB is a key mediator of the PNI-induced phenotypic alteration of spinal microglia and neuropathic pain development.
Collapse
Affiliation(s)
- Hidetoshi Tozaki-Saitoh
- Department of Life Innovation, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Junya Masuda
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Ryu Kawada
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Chinami Kojima
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Sosuke Yoneda
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Takahiro Masuda
- Department of Life Innovation, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Kazuhide Inoue
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Makoto Tsuda
- Department of Life Innovation, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| |
Collapse
|
5
|
Domínguez-Soto Á, Simón-Fuentes M, de Las Casas-Engel M, Cuevas VD, López-Bravo M, Domínguez-Andrés J, Saz-Leal P, Sancho D, Ardavín C, Ochoa-Grullón J, Sánchez-Ramón S, Vega MA, Corbí AL. IVIg Promote Cross-Tolerance against Inflammatory Stimuli In Vitro and In Vivo. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2018; 201:41-52. [PMID: 29743313 DOI: 10.4049/jimmunol.1701093] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 04/18/2018] [Indexed: 01/25/2023]
Abstract
IVIg is an approved therapy for immunodeficiency and for several autoimmune and inflammatory diseases. However, the molecular basis for the IVIg anti-inflammatory activity remains to be fully explained and cannot be extrapolated from studies on animal models of disease. We now report that IVIg impairs the generation of human monocyte-derived anti-inflammatory macrophages by inducing JNK activation and activin A production and limits proinflammatory macrophage differentiation by inhibiting GM-CSF-driven STAT5 activation. In vivo, IVIg provokes a rapid increase in peripheral blood activin A, CCL2, and IL-6 levels, an effect that can be recapitulated in vitro on human monocytes. On differentiating monocytes, IVIg promotes the acquisition of altered transcriptional and cytokine profiles, reduces TLR expression and signaling, and upregulates negative regulators of TLR-initiated intracellular signaling. In line with these effects, in vivo IVIg infusion induces a state tolerant toward subsequent stimuli that results in reduced inflammatory cytokine production after LPS challenge in human peripheral blood and significant protection from LPS-induced death in mice. Therefore, IVIg conditions human macrophages toward the acquisition of a state of cross-tolerance against inflammatory stimuli, an effect that correlates with the net anti-inflammatory action of IVIg in vivo.
Collapse
Affiliation(s)
- Ángeles Domínguez-Soto
- Departamento de Biología Celular, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Cientificas, 28040 Madrid, Spain;
| | - Miriam Simón-Fuentes
- Departamento de Biología Celular, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Cientificas, 28040 Madrid, Spain
| | - Mateo de Las Casas-Engel
- Departamento de Biología Celular, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Cientificas, 28040 Madrid, Spain
| | - Víctor D Cuevas
- Departamento de Biología Celular, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Cientificas, 28040 Madrid, Spain
| | - María López-Bravo
- Departamento de Inmunología y Oncología, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Cientificas, 28049 Madrid, Spain
| | - Jorge Domínguez-Andrés
- Departamento de Inmunología y Oncología, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Cientificas, 28049 Madrid, Spain
| | - Paula Saz-Leal
- Fundación Centro Nacional de Investigaciones Cardiovasculares, Centro Nacional de Investigaciones Cardiovasculares, 28029 Madrid, Spain; and
| | - David Sancho
- Fundación Centro Nacional de Investigaciones Cardiovasculares, Centro Nacional de Investigaciones Cardiovasculares, 28029 Madrid, Spain; and
| | - Carlos Ardavín
- Departamento de Inmunología y Oncología, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Cientificas, 28049 Madrid, Spain
| | - Juliana Ochoa-Grullón
- Departamento de Inmunología Clínica, Hospital Universitario Clínico San Carlos, 28040 Madrid, Spain
| | - Silvia Sánchez-Ramón
- Departamento de Inmunología Clínica, Hospital Universitario Clínico San Carlos, 28040 Madrid, Spain
| | - Miguel A Vega
- Departamento de Biología Celular, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Cientificas, 28040 Madrid, Spain
| | - Angel L Corbí
- Departamento de Biología Celular, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Cientificas, 28040 Madrid, Spain;
| |
Collapse
|
6
|
Riera-Borrull M, Cuevas VD, Alonso B, Vega MA, Joven J, Izquierdo E, Corbí ÁL. Palmitate Conditions Macrophages for Enhanced Responses toward Inflammatory Stimuli via JNK Activation. THE JOURNAL OF IMMUNOLOGY 2017; 199:3858-3869. [PMID: 29061766 DOI: 10.4049/jimmunol.1700845] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 09/22/2017] [Indexed: 12/13/2022]
Abstract
Obesity is associated with low-grade inflammation and elevated levels of circulating saturated fatty acids, which trigger inflammatory responses by engaging pattern recognition receptors in macrophages. Because tissue homeostasis is maintained through an adequate balance of pro- and anti-inflammatory macrophages, we assessed the transcriptional and functional profile of M-CSF-dependent monocyte-derived human macrophages exposed to concentrations of saturated fatty acids found in obese individuals. We report that palmitate (C16:0, 200 μM) significantly modulates the macrophage gene signature, lowers the expression of transcription factors that positively regulate IL-10 expression (MAFB, AhR), and promotes a proinflammatory state whose acquisition requires JNK activation. Unlike LPS, palmitate exposure does not activate STAT1, and its transcriptional effects can be distinguished from those triggered by LPS, as both agents oppositely regulate the expression of CCL19 and TRIB3 Besides, palmitate conditions macrophages for exacerbated proinflammatory responses (lower IL-10 and CCL2, higher TNF-α, IL-6, and IL-1β) toward pathogenic stimuli, a process also mediated by JNK activation. All of these effects of palmitate are fatty acid specific because oleate (C18:1, 200 μM) does not modify the macrophage transcriptional and functional profiles. Therefore, pathologic palmitate concentrations promote the acquisition of a specific polarization state in human macrophages and condition macrophages for enhanced responses toward inflammatory stimuli, with both effects being dependent on JNK activation. Our results provide further insight into the macrophage contribution to obesity-associated inflammation.
Collapse
Affiliation(s)
- Marta Riera-Borrull
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, 28040 Madrid, Spain; and.,Unitat de Recerca Biomèdica, Hospital Universitari Sant Joan, Institut d'Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, 43201 Reus, Spain
| | - Víctor D Cuevas
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, 28040 Madrid, Spain; and
| | - Bárbara Alonso
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, 28040 Madrid, Spain; and
| | - Miguel A Vega
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, 28040 Madrid, Spain; and
| | - Jorge Joven
- Unitat de Recerca Biomèdica, Hospital Universitari Sant Joan, Institut d'Investigació Sanitària Pere Virgili, Universitat Rovira i Virgili, 43201 Reus, Spain
| | - Elena Izquierdo
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, 28040 Madrid, Spain; and
| | - Ángel L Corbí
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, 28040 Madrid, Spain; and
| |
Collapse
|
7
|
Papaevgeniou N, Chondrogianni N. UPS Activation in the Battle Against Aging and Aggregation-Related Diseases: An Extended Review. Methods Mol Biol 2016; 1449:1-70. [PMID: 27613027 DOI: 10.1007/978-1-4939-3756-1_1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Aging is a biological process accompanied by gradual increase of damage in all cellular macromolecules, i.e., nucleic acids, lipids, and proteins. When the proteostasis network (chaperones and proteolytic systems) cannot reverse the damage load due to its excess as compared to cellular repair/regeneration capacity, failure of homeostasis is established. This failure is a major hallmark of aging and/or aggregation-related diseases. Dysfunction of the major cellular proteolytic machineries, namely the proteasome and the lysosome, has been reported during the progression of aging and aggregation-prone diseases. Therefore, activation of these pathways is considered as a possible preventive or therapeutic approach against the progression of these processes. This chapter focuses on UPS activation studies in cellular and organismal models and the effects of such activation on aging, longevity and disease prevention or reversal.
Collapse
Affiliation(s)
- Nikoletta Papaevgeniou
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Ave., Athens, 11635, Greece
| | - Niki Chondrogianni
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Ave., Athens, 11635, Greece.
| |
Collapse
|
8
|
Jung EJ, Park HC, Chung KH, Kim CW. Proteomic analysis of SP600125-controlled TrkA-dependent targets in SK-N-MC neuroblastoma cells: inhibition of TrkA activity by SP600125. Proteomics 2014; 14:202-15. [PMID: 24375967 DOI: 10.1002/pmic.201300023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 11/13/2013] [Accepted: 12/01/2013] [Indexed: 12/12/2022]
Abstract
The c-Jun N-terminal kinase (JNK) is well known to play an important role in cell death signaling of the p75 neurotrophin receptor. However, little has been studied about a role of JNK in the signaling pathways of the tropomyosin-related kinase A (TrkA) neurotrophin receptor. In this study, we investigated JNK inhibitor SP600125-controlled TrkA-dependent targets by proteomic analysis to better understand an involvement of JNK in TrkA-mediated signaling pathways. PDQuest image analysis and protein identification results showed that hnRNP C1/C2, α-tubulin, β-tubulin homolog, actin homolog, and eIF-5A-1 protein spots were upregulated by ectopic expression of TrkA, whereas α-enolase, peroxiredoxin-6, PROS-27, HSP70, PP1-gamma, and PDH E1-alpha were downregulated by TrkA, and these TrkA-dependent upregulation and downregulation were significantly suppressed by SP600125. Notably, TrkA largely affected certain PTM(s) but not total protein amounts of the SP600125-controlled TrkA-dependent targets. Moreover, SP600125 strongly suppressed TrkA-mediated tyrosine phosphorylation signaling pathways as well as JNK signaling, indicating that SP600125 could function as a TrkA inhibitor. Taken together, our results suggest that TrkA could play an important role in the cytoskeleton, cell death, cellular processing, and glucose metabolism through activation or inactivation of the SP600125-controlled TrkA-dependent targets.
Collapse
Affiliation(s)
- Eun Joo Jung
- Department of Biochemistry, Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju, South Korea
| | | | | | | |
Collapse
|
9
|
Tuvshintugs B, Sato T, Enkhtuya R, Yamashita K, Yoshioka K. JSAP1 and JLP are required for ARF6 localization to the midbody in cytokinesis. Genes Cells 2014; 19:692-703. [DOI: 10.1111/gtc.12170] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 06/23/2014] [Indexed: 01/23/2023]
Affiliation(s)
- Baljinnyam Tuvshintugs
- Division of Molecular Cell Signaling; Cancer Research Institute; Kanazawa University; Kanazawa 920-1192 Japan
| | - Tokiharu Sato
- Division of Molecular Cell Signaling; Cancer Research Institute; Kanazawa University; Kanazawa 920-1192 Japan
| | - Radnaa Enkhtuya
- Division of Molecular Cell Signaling; Cancer Research Institute; Kanazawa University; Kanazawa 920-1192 Japan
| | - Katsumi Yamashita
- Division of Pharmaceutical Sciences; Institute of Medical; Pharmaceutical and Health Sciences; Kanazawa University; Kanazawa 920-1192 Japan
| | - Katsuji Yoshioka
- Division of Molecular Cell Signaling; Cancer Research Institute; Kanazawa University; Kanazawa 920-1192 Japan
| |
Collapse
|
10
|
Efficient Keratinocyte Differentiation Strictly Depends on JNK-Induced Soluble Factors in Fibroblasts. J Invest Dermatol 2014; 134:1332-1341. [DOI: 10.1038/jid.2013.535] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 11/14/2013] [Accepted: 11/16/2013] [Indexed: 12/21/2022]
|
11
|
Liao CK, Jeng CJ, Wang HS, Wang SH, Wu JC. Lipopolysaccharide induces degradation of connexin43 in rat astrocytes via the ubiquitin-proteasome proteolytic pathway. PLoS One 2013; 8:e79350. [PMID: 24236122 PMCID: PMC3827358 DOI: 10.1371/journal.pone.0079350] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 09/30/2013] [Indexed: 11/20/2022] Open
Abstract
The astrocytic syncytium plays a critical role in maintaining the homeostasis of the brain through the regulation of gap junction intercellular communication (GJIC). Changes to GJIC in response to inflammatory stimuli in astrocytes may have serious effects on the brain. We have previously shown that lipopolysaccharide (LPS) reduces connexin43 (Cx43) expression and GJIC in cultured rat astrocytes via a toll-like receptor 4-mediated signaling pathway. In the present study, treatment of astrocytes with LPS resulted in a significant increase in levels of the phosphorylated forms of stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) -1, -2, and -3 for up to 18 h. An increase in nuclear transcription factor NF-κB levels was also observed after 8 h of LPS treatment and was sustained for up to 18 h. The LPS-induced decrease in Cx43 protein levels and inhibition of GJIC were blocked by the SAPK/JNK inhibitor SP600125, but not by the NF-κB inhibitor BAY11-7082. Following blockade of de novo protein synthesis by cycloheximide, LPS accelerated Cx43 degradation. Moreover, the LPS-induced downregulation of Cx43 was blocked following inhibition of 26S proteasome activity using the reversible proteasome inhibitor MG132 or the irreversible proteasome inhibitor lactacystin. Immunoprecipitation analyses revealed an increased association of Cx43 with both ubiquitin and E3 ubiquitin ligase Nedd4 in astrocytes after LPS stimulation for 6 h and this effect was prevented by SP600125. Taken together, these results suggest that LPS stimulation leads to downregulation of Cx43 expression and GJIC in rat astrocytes by activation of SAPK/JNK and the ubiquitin-proteasome proteolytic pathway.
Collapse
Affiliation(s)
- Chih-Kai Liao
- Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chung-Jiuan Jeng
- Institute of Anatomy and Cell Biology, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Hwai-Shi Wang
- Institute of Anatomy and Cell Biology, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Shu-Huei Wang
- Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Jiahn-Chun Wu
- Institute of Anatomy and Cell Biology, School of Medicine, National Yang-Ming University, Taipei, Taiwan
- * E-mail:
| |
Collapse
|