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Ildarabadi A, Mir Mohammad Ali SN, Rahmani F, Mosavari N, Pourbakhtyaran E, Rezaei N. Inflammation and oxidative stress in epileptic children: from molecular mechanisms to clinical application of ketogenic diet. Rev Neurosci 2024; 35:473-488. [PMID: 38347675 DOI: 10.1515/revneuro-2023-0128] [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: 10/15/2023] [Accepted: 12/18/2023] [Indexed: 06/02/2024]
Abstract
Childhood epilepsy affects up to 1 % of children. It has been shown that 30 % of patients are resistant to drug treatments, making further investigation of other potential treatment strategies necessary. One such approach is the ketogenic diet (KD) showing promising results and potential benefits beyond the use of current antiepileptic drugs. This study aims to investigate the effects of KD on inflammation and oxidative stress, as one of the main suggested mechanisms of neuroprotection, in children with epilepsy. This narrative review was conducted using the Medline and Google Scholar databases, and by searching epilepsy, drug-resistant epilepsy, child, children, ketogenic, ketogenic diet, diet, ketogenic, keto, ketone bodies (BHB), PUFA, gut microbiota, inflammation, inflammation mediators, neurogenic inflammation, neuroinflammation, inflammatory marker, adenosine modulation, mitochondrial function, MTOR pathway, Nrf2 pathway, mitochondrial dysfunction, PPARɣ, oxidative stress, ROS/RNS, and stress oxidative as keywords. Compelling evidence underscores inflammation and oxidative stress as pivotal factors in epilepsy, even in cases with genetic origins. The ketogenic diet effectively addresses these factors by reducing ROS and RNS, enhancing antioxidant defenses, improving mitochondrial function, and regulating inflammatory genes. Additionally, KD curbs pro-inflammatory cytokine and chemokine production by dampening NF-κB activation, inhibiting the NLRP3 inflammasome, increasing brain adenosine levels, mTOR pathway inhibition, upregulating PPARɣ expression, and promoting a healthy gut microbiota while emphasizing the consumption of healthy fats. KD could be considered a promising therapeutic intervention in patients with epilepsy particularly in drug-resistant epilepsy cases, due to its targeted approach addressing oxidative stress and inflammatory mechanisms.
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Affiliation(s)
- Azam Ildarabadi
- Department of Nutrition Science, Science and Research Branch, Faculty of Medical Science and Technology, Islamic Azad University, Shodada Hesarak Blvd, Tehran 1477893855, Iran
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Dr. Qarib St, Tehran 1419733151, Iran
| | - Seyedeh Nooshan Mir Mohammad Ali
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Dr. Qarib St, Tehran 1419733151, Iran
- Department of Food, Nutrition, Dietetics and Health, Kansas State University, Manhattan, KS 66502, USA
| | - Fatemeh Rahmani
- Department of Nutrition Science, Science and Research Branch, Faculty of Medical Science and Technology, Islamic Azad University, Shodada Hesarak Blvd, Tehran 1477893855, Iran
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Dr. Qarib St, Tehran 1419733151, Iran
| | - Narjes Mosavari
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Dr. Qarib St, Tehran 1419733151, Iran
| | - Elham Pourbakhtyaran
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Dr. Qarib St, Tehran 1419733151, Iran
- Department of Pediatric Neurology, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Dr. Qarib St, Tehran 1419733151, Iran
| | - Nima Rezaei
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Dr. Qarib St, Tehran 1419733151, Iran
- Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center Hospital, Tehran University of Medical Sciences, Dr. Qarib St, Tehran 1419733151, Iran
- Department of Immunology, School of Medicine, Tehran University of Medical Science, Pour Sina St, Tehran 1461884513, Iran
- Research Center for Immunodeficiencies, Children's Medical Center Hospital, Dr. Qarib St, Keshavarz Blvd, Tehran 14194, Iran
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Differential Expression of Prostaglandin Receptors in Canine Uterus with Pyometra. Top Companion Anim Med 2021; 46:100612. [PMID: 34742880 DOI: 10.1016/j.tcam.2021.100612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 10/25/2021] [Accepted: 10/29/2021] [Indexed: 11/22/2022]
Abstract
The objective of the study was to ascertain the role of prostaglandins Viz., PGE2 and PGF2α, and their respective receptors in the pathophysiology of canine pyometra. Normal (n=6) and pyometra (n=8) affected uterus were collected from bitches undergoing ovariohysterectomy. Pyometra was graded according to histopathological alterations. The levels of PGE2 and PGF2α were estimated in the endometrium. The differential expression in the mRNA of PGF2α receptor (FP) and PGE2 receptors (EP1, EP2, EP3, and EP4) were studied in the endometrium and myometrium of the pyometra-affected uterus. Normal uterus served as calibrator. Elevation of both PGE2 and PGF2α levels in the endometrium of pyometra-affected bitches was observed. The FP receptor gene in the endometrium and myometrium of pyometra-affected bitches was down-regulated (P<0.05). Out of all EP receptors, only EP2 receptor has shown up-regulation in both endometrium and myometrium of pyometra affected uterus. EP3 receptor got down-regulated in both endometrium and myometrium in pyometra. Thus, down-regulation of FP, EP3 receptors in the myometrium reinforces the lack of contractility in pyometra-affected bitches favoring bacterial proliferation and subsequent pus accumulation. Moreover, upregulation of EP2 receptors in the pyometra bitches suggests the scope of selective pharmacological inhibition of EP2 receptors as an adjunct therapy in the treatment of pyometra.
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Recabarren-Leiva D, Alarcón M. New insights into the gene expression associated to amyotrophic lateral sclerosis. Life Sci 2018; 193:110-123. [DOI: 10.1016/j.lfs.2017.12.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Revised: 12/01/2017] [Accepted: 12/10/2017] [Indexed: 12/11/2022]
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Hennequart M, Pilotte L, Cane S, Hoffmann D, Stroobant V, Plaen ED, Van den Eynde B. Constitutive IDO1 Expression in Human Tumors Is Driven by Cyclooxygenase-2 and Mediates Intrinsic Immune Resistance. Cancer Immunol Res 2017; 5:695-709. [PMID: 28765120 DOI: 10.1158/2326-6066.cir-16-0400] [Citation(s) in RCA: 122] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 05/02/2017] [Accepted: 06/30/2017] [Indexed: 12/16/2022]
Abstract
Tumors use various mechanisms to avoid immune destruction. Cyclooxygenase-2 (COX-2) expression may be a driver of immune suppression in melanoma, but the mechanisms involved remain elusive. Here, we show that COX-2 expression drives constitutive expression of indoleamine 2,3-dioxygenase 1 (IDO1) in human tumor cells. IDO1 is an immunosuppressive enzyme that degrades tryptophan. In a series of seven human tumor lines, constitutive IDO1 expression depends on COX-2 and prostaglandin E2 (PGE2), which, upon autocrine signaling through the EP receptor, activates IDO1 via the PKC and PI3K pathways. COX-2 expression itself depends on the MAPK pathway, which therefore indirectly controls IDO1 expression. Most of these tumors carry PI3K or MAPK oncogenic mutations, which may favor constitutive IDO1 expression. Celecoxib treatment promoted immune rejection of IDO1-expressing human tumor xenografts in immunodeficient mice reconstituted with human allogeneic lymphocytes. This effect was associated with a reduced expression of IDO1 in those ovarian SKOV3 tumors and an increased infiltration of CD3+ and CD8+ cells. Our results highlight the role of COX-2 in constitutive IDO1 expression by human tumors and substantiate the use of COX-2 inhibitors to improve the efficacy of cancer immunotherapy, by reducing constitutive IDO1 expression, which contributes to the lack of T-cell infiltration in "cold" tumors, which fail to respond to immunotherapy. Cancer Immunol Res; 5(8); 695-709. ©2017 AACR.
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Affiliation(s)
- Marc Hennequart
- Ludwig Institute for Cancer Research, Brussels, Belgium.,de Duve Institute, Université catholique de Louvain, Brussels, Belgium
| | - Luc Pilotte
- Ludwig Institute for Cancer Research, Brussels, Belgium.,de Duve Institute, Université catholique de Louvain, Brussels, Belgium
| | - Stefania Cane
- Ludwig Institute for Cancer Research, Brussels, Belgium.,de Duve Institute, Université catholique de Louvain, Brussels, Belgium
| | - Delia Hoffmann
- Ludwig Institute for Cancer Research, Brussels, Belgium.,de Duve Institute, Université catholique de Louvain, Brussels, Belgium
| | - Vincent Stroobant
- Ludwig Institute for Cancer Research, Brussels, Belgium.,de Duve Institute, Université catholique de Louvain, Brussels, Belgium
| | - Etienne De Plaen
- Ludwig Institute for Cancer Research, Brussels, Belgium.,de Duve Institute, Université catholique de Louvain, Brussels, Belgium
| | - Benoît Van den Eynde
- Ludwig Institute for Cancer Research, Brussels, Belgium. .,de Duve Institute, Université catholique de Louvain, Brussels, Belgium.,Walloon Excellence in Life Sciences and Biotechnology, Brussels, Belgium
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van den Akker GGH, Surtel DAM, Cremers A, Hoes MFGA, Caron MM, Richardson SM, Rodrigues-Pinto R, van Rhijn LW, Hoyland JA, Welting TJM, Voncken JW. EGR1 controls divergent cellular responses of distinctive nucleus pulposus cell types. BMC Musculoskelet Disord 2016; 17:124. [PMID: 26975996 PMCID: PMC4791893 DOI: 10.1186/s12891-016-0979-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 03/09/2016] [Indexed: 01/07/2023] Open
Abstract
Background Immediate early genes (IEGs) encode transcription factors which serve as first line response modules to altered conditions and mediate appropriate cell responses. The immediate early response gene EGR1 is involved in physiological adaptation of numerous different cell types. We have previously shown a role for EGR1 in controlling processes supporting chondrogenic differentiation. We recently established a unique set of phenotypically distinct cell lines from the human nucleus pulposus (NP). Extensive characterization showed that these NP cellular subtypes represented progenitor-like cell types and more functionally mature cells. Methods To further understanding of cellular heterogeneity in the NP, we analyzed the response of these cell subtypes to anabolic and catabolic factors. Here, we test the hypothesis that physiological responses of distinct NP cell types are mediated by EGR1 and reflect specification of cell function using an RNA interference-based experimental approach. Results We show that distinct NP cell types rapidly induce EGR1 exposure to either growth factors or inflammatory cytokines. In addition, we show that mRNA profiles induced in response to anabolic or catabolic conditions are cell type specific: the more mature NP cell type produced a strong and more specialized transcriptional response to IL-1β than the NP progenitor cells and aspects of this response were controlled by EGR1. Conclusions Our current findings provide important substantiation of differential functionality among NP cellular subtypes. Additionally, the data shows that early transcriptional programming initiated by EGR1 is essentially restrained by the cells’ epigenome as it was determined during development and differentiation. These studies begin to define functional distinctions among cells of the NP and will ultimately contribute to defining functional phenotypes within the adult intervertebral disc. Electronic supplementary material The online version of this article (doi:10.1186/s12891-016-0979-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Guus G H van den Akker
- Department of Orthopaedic Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands.,Department of Molecular Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands.,Current Address: Department of Experimental Rheumatology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Don A M Surtel
- Department of Orthopaedic Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Andy Cremers
- Department of Orthopaedic Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Martijn F G A Hoes
- Department of Molecular Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Marjolein M Caron
- Department of Orthopaedic Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Stephen M Richardson
- Centre for Tissue Injury and Repair, Institute of Inflammation and Repair, The University of Manchester, Manchester, UK
| | - Ricardo Rodrigues-Pinto
- Centre for Tissue Injury and Repair, Institute of Inflammation and Repair, The University of Manchester, Manchester, UK.,Current Address: Department of Orthopaedics, Centro Hospitalar do Porto - Hospital de Santo António, Porto, Portugal
| | - Lodewijk W van Rhijn
- Department of Orthopaedic Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Judith A Hoyland
- Centre for Tissue Injury and Repair, Institute of Inflammation and Repair, The University of Manchester, Manchester, UK.,NIHR Manchester Musculoskeletal Biomedical Research Unit, Manchester Academic Health Science Centre, Manchester, UK
| | - Tim J M Welting
- Department of Orthopaedic Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Jan Willem Voncken
- Department of Molecular Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands.
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Koeberle A, Werz O. Perspective of microsomal prostaglandin E2 synthase-1 as drug target in inflammation-related disorders. Biochem Pharmacol 2015; 98:1-15. [PMID: 26123522 DOI: 10.1016/j.bcp.2015.06.022] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 06/23/2015] [Indexed: 02/07/2023]
Abstract
Prostaglandin (PG)E2 encompasses crucial roles in pain, fever, inflammation and diseases with inflammatory component, such as cancer, but is also essential for gastric, renal, cardiovascular and immune homeostasis. Cyclooxygenases (COX) convert arachidonic acid to the intermediate PGH2 which is isomerized to PGE2 by at least three different PGE2 synthases. Inhibitors of COX - non-steroidal anti-inflammatory drugs (NSAIDs) - are currently the only available therapeutics that target PGE2 biosynthesis. Due to adverse effects of COX inhibitors on the cardiovascular system (COX-2-selective), stomach and kidney (COX-1/2-unselective), novel pharmacological strategies are in demand. The inducible microsomal PGE2 synthase (mPGES)-1 is considered mainly responsible for the excessive PGE2 synthesis during inflammation and was suggested as promising drug target for suppressing PGE2 biosynthesis. However, 15 years after intensive research on the biology and pharmacology of mPGES-1, the therapeutic value of mPGES-1 as drug target is still vague and mPGES-1 inhibitors did not enter the market so far. This commentary will first shed light on the structure, mechanism and regulation of mPGES-1 and will then discuss its biological function and the consequence of its inhibition for the dynamic network of eicosanoids. Moreover, we (i) present current strategies for interfering with mPGES-1-mediated PGE2 synthesis, (ii) summarize bioanalytical approaches for mPGES-1 drug discovery and (iii) describe preclinical test systems for the characterization of mPGES-1 inhibitors. The pharmacological potential of selective mPGES-1 inhibitor classes as well as dual mPGES-1/5-lipoxygenase inhibitors is reviewed and pitfalls in their development, including species discrepancies and loss of in vivo activity, are discussed.
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Affiliation(s)
- Andreas Koeberle
- Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, Philosophenweg 14, 07743 Jena, Germany.
| | - Oliver Werz
- Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, Philosophenweg 14, 07743 Jena, Germany.
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Role of inflammatory mediators in the pathogenesis of epilepsy. Mediators Inflamm 2014; 2014:901902. [PMID: 25197169 PMCID: PMC4147258 DOI: 10.1155/2014/901902] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 08/04/2014] [Accepted: 08/05/2014] [Indexed: 01/10/2023] Open
Abstract
Epilepsy is one of the most common chronic brain disorders worldwide, affecting 1% of people across different ages and backgrounds. Epilepsy is defined as the sporadic occurrence of spontaneous recurrent seizures. Accumulating preclinical and clinical evidence suggest that there is a positive feedback cycle between epileptogenesis and brain inflammation. Epileptic seizures increase key inflammatory mediators, which in turn cause secondary damage to the brain and increase the likelihood of recurrent seizures. Cytokines and prostaglandins are well-known inflammatory mediators in the brain, and their biosynthesis is enhanced following seizures. Such inflammatory mediators could be therapeutic targets for the development of new antiepileptic drugs. In this review, we discuss the roles of inflammatory mediators in epileptogenesis.
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Xia H, Wang C, Chen W, Zhang H, Chaudhury L, Zhou Z, Liu R, Chen C. Kruppel-like factor 5 transcription factor promotes microsomal prostaglandin E2 synthase 1 gene transcription in breast cancer. J Biol Chem 2013; 288:26731-40. [PMID: 23913682 DOI: 10.1074/jbc.m113.483958] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The KLF5 (Krüppel-like factor 5) transcription factor is specifically expressed in a subset of estrogen receptor α-negative breast cancers. Although KLF5 promotes breast cancer cell cycle progression, survival, and tumorigenesis, the mechanism by which KLF5 promotes breast cancer is still not entirely understood. Here, we demonstrate that mPGES1, encoding microsomal prostaglandin E2 synthase 1 (mPGES1), is a KLF5 direct downstream target gene. KLF5 overexpression or knockdown positively altered the levels of mPGES1 mRNA and protein in multiple breast cell lines. 12-O-Tetradecanoylphorbol-13-acetate induced the expression of both KLF5 and mPGES1 in dosage- and time-dependent manners. The induction of KLF5 was essential for 12-O-tetradecanoylphorbol-13-acetate to induce mPGES1 expression. Additionally, KLF5 bound to the mPGES1 gene proximal promoter and activated its transcription. Both KLF5 and mPGES1 promoted prostaglandin E2 production; regulated p21, p27, and Survivin downstream gene expression; and likewise stimulated cell proliferation. Overexpression of mPGES1 partially rescued the KLF5 knockdown-induced downstream gene expression changes and growth arrest in MCF10A cells. Finally, we demonstrate that the expression of mPGES1 was positively correlated with the estrogen receptor α/progesterone receptor/HER2 triple-negative status. These findings suggest that mPGES1 is a target gene of KLF5, making it a new biomarker and a potential therapeutic target for triple-negative breast cancers.
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Affiliation(s)
- Houjun Xia
- From the Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences and Yunnan Province, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
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Bickford JS, Beachy DE, Newsom KJ, Barilovits SJ, Herlihy JDH, Qiu X, Walters JN, Li N, Nick HS. A distal enhancer controls cytokine-dependent human cPLA2α gene expression. J Lipid Res 2013; 54:1915-26. [PMID: 23549331 DOI: 10.1194/jlr.m037382] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Specific control of group IVA cytosolic phospholipase A2 (cPLA2α or PLA2G4A) expression modulates arachidonic acid production, thus tightly regulating the downstream effects of pro- and anti-inflammatory eicosanoids. The significance of this pathway in human disease is apparent in a range of pathologies from inflammation to tumorigenesis. While much of the regulation of cPLA2α has focused on posttranslational phosphorylation of the protein, studies on transcriptional regulation of this gene have focused only on proximal promoter regions. We have identified a DNase I hypersensitive site encompassing a 5' distal enhancer element containing a highly conserved consensus AP-1 site involved in transcriptional activation of cPLA2α by interleukin (IL)-1β. Chromatin immunoprecipitation (ChIP), knockdown, knockout, and overexpression analyses have shown that c-Jun acts both in a negative and positive regulatory role. Transcriptional activation of cPLA2α occurs through the phosphorylation of c-Jun in conjunction with increased association of C/EBPβ with the distal novel enhancer. The association of C/EBPβ with the transcriptional activation complex does not require an obvious DNA binding site. These data provide new and important contributions to the understanding of cPLA2α regulation at the transcriptional level, with implications for eicosanoid metabolism, cellular signaling, and disease pathogenesis.
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Affiliation(s)
- Justin S Bickford
- Department of Neuroscience, University of Florida, Gainesville, FL, USA
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Spaapen F, van den Akker GGH, Caron MMJ, Prickaerts P, Rofel C, Dahlmans VEH, Surtel DAM, Paulis Y, Schweizer F, Welting TJM, Eijssen LM, Voncken JW. The immediate early gene product EGR1 and polycomb group proteins interact in epigenetic programming during chondrogenesis. PLoS One 2013; 8:e58083. [PMID: 23483971 PMCID: PMC3590300 DOI: 10.1371/journal.pone.0058083] [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: 07/25/2012] [Accepted: 01/30/2013] [Indexed: 12/18/2022] Open
Abstract
Initiation of and progression through chondrogenesis is driven by changes in the cellular microenvironment. At the onset of chondrogenesis, resting mesenchymal stem cells are mobilized in vivo and a complex, step-wise chondrogenic differentiation program is initiated. Differentiation requires coordinated transcriptomic reprogramming and increased progenitor proliferation; both processes require chromatin remodeling. The nature of early molecular responses that relay differentiation signals to chromatin is poorly understood. We here show that immediate early genes are rapidly and transiently induced in response to differentiation stimuli in vitro. Functional ablation of the immediate early factor EGR1 severely deregulates expression of key chondrogenic control genes at the onset of differentiation. In addition, differentiating cells accumulate DNA damage, activate a DNA damage response and undergo a cell cycle arrest and prevent differentiation associated hyper-proliferation. Failed differentiation in the absence of EGR1 affects global acetylation and terminates in overall histone hypermethylation. We report novel molecular connections between EGR1 and Polycomb Group function: Polycomb associated histone H3 lysine27 trimethylation (H3K27me3) blocks chromatin access of EGR1. In addition, EGR1 ablation results in abnormal Ezh2 and Bmi1 expression. Consistent with this functional interaction, we identify a number of co-regulated targets genes in a chondrogenic gene network. We here describe an important role for EGR1 in early chondrogenic epigenetic programming to accommodate early gene-environment interactions in chondrogenesis.
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Affiliation(s)
- Frank Spaapen
- Department of Molecular Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Guus G. H. van den Akker
- Department of Molecular Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Marjolein M. J. Caron
- Department of Orthopaedic Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Peggy Prickaerts
- Department of Molecular Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Celine Rofel
- Department of Molecular Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Vivian E. H. Dahlmans
- Department of Molecular Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Don A. M. Surtel
- Department of Orthopaedic Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Yvette Paulis
- Department of Molecular Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Finja Schweizer
- Department of Orthopaedic Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Tim J. M. Welting
- Department of Orthopaedic Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Lars M. Eijssen
- Department of Bioinformatics – BiGCaT, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Jan Willem Voncken
- Department of Molecular Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands
- * E-mail:
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