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Sun Z, Zhang W, Li J, Yang K, Zhang Y, Li Z. H9N2 Avian Influenza Virus Downregulates FcRY Expression in Chicken Macrophage Cell Line HD11 by Activating the JNK MAPK Pathway. Int J Mol Sci 2024; 25:2650. [PMID: 38473897 DOI: 10.3390/ijms25052650] [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: 12/19/2023] [Revised: 02/02/2024] [Accepted: 02/06/2024] [Indexed: 03/14/2024] Open
Abstract
The H9N2 avian influenza virus causes reduced production performance and immunosuppression in chickens. The chicken yolk sac immunoglobulins (IgY) receptor (FcRY) transports from the yolk into the embryo, providing offspring with passive immunity to infection against common poultry pathogens. FcRY is expressed in many tissues/organs of the chicken; however, there are no reports investigating FcRY expression in chicken macrophage cells, and how H9N2-infected HD11 cells (a chicken macrophage-like cell line) regulate FcRY expression remains uninvestigated. This study used the H9N2 virus as a model pathogen to explore the regulation of FcRY expression in avian macrophages. FcRY was highly expressed in HD11 cells, as shown by reverse transcription polymerase chain reactions, and indirect immunofluorescence indicated that FcRY was widely expressed in HD11 cells. HD11 cells infected with live H9N2 virus exhibited downregulated FcRY expression. Transfection of eukaryotic expression plasmids encoding each viral protein of H9N2 into HD11 cells revealed that nonstructural protein (NS1) and matrix protein (M1) downregulated FcRY expression. In addition, the use of a c-jun N-terminal kinase (JNK) activator inhibited the expression of FcRY, while a JNK inhibitor antagonized the downregulation of FcRY expression by live H9N2 virus, NS1 and M1 proteins. Finally, a dual luciferase reporter system showed that both the M1 protein and the transcription factor c-jun inhibited FcRY expression at the transcriptional level. Taken together, the transcription factor c-jun was a negative regulator of FcRY, while the live H9N2 virus, NS1, and M1 proteins downregulated the FcRY expression through activating the JNK signaling pathway. This provides an experimental basis for a novel mechanism of immunosuppression in the H9N2 avian influenza virus.
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Affiliation(s)
- Zhijian Sun
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan 430070, China
| | - Wenjie Zhang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan 430070, China
| | - Jian Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan 430070, China
| | - Kang Yang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan 430070, China
| | - Yanhao Zhang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan 430070, China
| | - Zili Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Wuhan 430070, China
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2
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Lien CF, Chen SJ, Tsai MC, Lin CS. Potential Role of Protein Kinase C in the Pathophysiology of Diabetes-Associated Atherosclerosis. Front Pharmacol 2021; 12:716332. [PMID: 34276388 PMCID: PMC8283198 DOI: 10.3389/fphar.2021.716332] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 06/22/2021] [Indexed: 12/13/2022] Open
Abstract
Diabetes mellitus is a metabolic syndrome that affects millions of people worldwide. Recent studies have demonstrated that protein kinase C (PKC) activation plays an important role in hyperglycemia-induced atherosclerosis. PKC activation is involved in several cellular responses such as the expression of various growth factors, activation of signaling pathways, and enhancement of oxidative stress in hyperglycemia. However, the role of PKC activation in pro-atherogenic and anti-atherogenic mechanisms remains controversial, especially under hyperglycemic condition. In this review, we discuss the role of different PKC isoforms in lipid regulation, oxidative stress, inflammatory response, and apoptosis. These intracellular events are linked to the pathogenesis of atherosclerosis in diabetes. PKC deletion or treatment with PKC inhibitors has been studied in the regulation of atherosclerotic plaque formation and evolution. Furthermore, some preclinical and clinical studies have indicated that PKCβ and PKCδ are potential targets for the treatment of diabetic vascular complications. The current review summarizes these multiple signaling pathways and cellular responses regulated by PKC activation and the potential therapeutic targets of PKC in diabetic complications.
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Affiliation(s)
- Chih-Feng Lien
- Division of Cardiology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Sy-Jou Chen
- Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Min-Chien Tsai
- Department of Physiology and Biophysics, Graduate Institute of Physiology, National Defense Medical Center, Taipei, Taiwan
| | - Chin-Sheng Lin
- Division of Cardiology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
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3
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Giglio RV, Carruba G, Cicero AF, Banach M, Patti AM, Nikolic D, Cocciadiferro L, Zarcone M, Montalto G, Stoian AP, Banerjee Y, Rizvi AA, Toth PP, Rizzo M. Pasta Supplemented with Opuntia ficus-indica Extract Improves Metabolic Parameters and Reduces Atherogenic Small Dense Low-Density Lipoproteins in Patients with Risk Factors for the Metabolic Syndrome: A Four-Week Intervention Study. Metabolites 2020; 10:metabo10110428. [PMID: 33114614 PMCID: PMC7694062 DOI: 10.3390/metabo10110428] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 10/19/2020] [Accepted: 10/20/2020] [Indexed: 12/24/2022] Open
Abstract
Food supplementation with Opuntia ficus-indica (OFI) has been associated with a significant reduction in total cholesterol, body fat, hyperglycemia and blood pressure. Since OFI may also have antioxidant and anti-atherogenic properties, we hypothesized that its supplementation might reduce atherogenic lipoproteins, including small, dense low-density lipoproteins (sdLDL). Forty-nine patients (13 men and 36 women, mean age: 56 ± 5 years) with one or two criteria for the metabolic syndrome weekly consumed 500 g of pasta supplemented with 3% OFI extract (30% of insoluble polysaccharides with high antioxidant power) for 1 month. The full LDL subclass profile was assessed by gel electrophoresis (Lipoprint, Quantimetrix, Redondo Beach, CA, USA). After 1 month of pasta supplementation, waist circumference (p = 0.0297), plasma glucose (p < 0.0001), triglycerides (p = 0.0137), plasma creatinine (p = 0.0244), urea and aspartate transaminase (p < 0.0001 for each) significantly decreased. A percentage increase in larger, less atherogenic LDL-1 (p = 0.0002), with a concomitant reduction in smaller, denser LDL-2 (p < 0.0001) and LDL-3 (p = 0.0004), were found. LDL-4 and-5 decreased, although not significantly. This is the first intervention study suggesting that pasta enriched with an OFI extract may have beneficial effects on some metabolic parameters and the LDL particle sizes, reducing atherogenic sdLDL. Future studies will help to establish if these findings impact cardiovascular outcomes.
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Affiliation(s)
- Rosaria Vincenza Giglio
- Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties (PROMISE), University of Palermo, 90127 Palermo, Italy; (R.V.G.); (A.M.P.); (G.M.); (M.R.)
| | - Giuseppe Carruba
- Division of Research and Internationalization, ARNAS-Civico Di Cristina e Benfratelli, 90127 Palermo, Italy; (G.C.); (L.C.); (M.Z.)
| | - Arrigo F.G. Cicero
- Medical and Surgical Sciences Department, Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy;
| | - Maciej Banach
- Department of Hypertension, WAM University Hospital in Lodz, Medical University of Lodz, 90-419 Lodz, Poland;
- Polish Mother’s Memorial Hospital Research Institute (PMMHRI) in Lodz, 93-338 Lodz, Poland
| | - Angelo Maria Patti
- Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties (PROMISE), University of Palermo, 90127 Palermo, Italy; (R.V.G.); (A.M.P.); (G.M.); (M.R.)
| | - Dragana Nikolic
- Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties (PROMISE), University of Palermo, 90127 Palermo, Italy; (R.V.G.); (A.M.P.); (G.M.); (M.R.)
- Correspondence: ; Tel.: +39-091-655-4703
| | - Letizia Cocciadiferro
- Division of Research and Internationalization, ARNAS-Civico Di Cristina e Benfratelli, 90127 Palermo, Italy; (G.C.); (L.C.); (M.Z.)
| | - Maurizio Zarcone
- Division of Research and Internationalization, ARNAS-Civico Di Cristina e Benfratelli, 90127 Palermo, Italy; (G.C.); (L.C.); (M.Z.)
| | - Giuseppe Montalto
- Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties (PROMISE), University of Palermo, 90127 Palermo, Italy; (R.V.G.); (A.M.P.); (G.M.); (M.R.)
| | - Anca Pantea Stoian
- Department of Diabetes, Nutrition and Metabolic Diseases, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania;
| | - Yajnavalka Banerjee
- Department of Biochemistry, Mohammed Bin Rashid University of Medicine and Health Sciences, 505055 Dubai, UAE;
| | - Ali A. Rizvi
- Division of Endocrinology, Diabetes and Metabolism, University of South Carolina School of Medicine, Columbia, SC 29203, USA;
- Division of Endocrinology, Metabolism, and Lipids, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Peter P. Toth
- CGH Medical Center, Sterling, IL 61081, USA;
- School of Medicine, University of Illinois, Peoria, IL 60612, USA
- School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Manfredi Rizzo
- Department of Health Promotion Sciences Maternal and Infantile Care, Internal Medicine and Medical Specialties (PROMISE), University of Palermo, 90127 Palermo, Italy; (R.V.G.); (A.M.P.); (G.M.); (M.R.)
- Division of Endocrinology, Diabetes and Metabolism, University of South Carolina School of Medicine, Columbia, SC 29203, USA;
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Kubota S, Tanaka Y, Nagaoka S. Ellagic acid affects mRNA expression levels of genes that regulate cholesterol metabolism in HepG2 cells. Biosci Biotechnol Biochem 2019; 83:952-959. [PMID: 30741106 DOI: 10.1080/09168451.2019.1576498] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Ellagic acid has been shown to improve cholesterol metabolism in animal studies, but the molecular mechanisms underlying this function have not been fully understood. We performed DNA microarray analysis to elucidate the effects of ellagic acid on cholesterol metabolism in HepG2 hepatocytes. This revealed that the expression levels of several genes related to cholesterol metabolism, including the low-density lipoprotein receptor (LDLR), were changed by ellagic acid treatment. Using a real-time PCR and immunoblot we confirmed that ellagic acid treatment up-regulated mRNA and protein expression level of the LDLR. Moreover, In the presence of 25 μM ellagic acid, extracellular apoB protein and MTP mRNA levels were significantly decreased. These findings indicate that ellagic acid improves cholesterol metabolism through the up-regulation of LDLR, down-regulation of MTP mRNA and reduces extracellular apoB levels. The ellagic acid-induced up-regulation of LDLR occurred via the extracellular signal-regulated kinase (ERK) signaling pathway in HepG2 hepatocytes. Abbreviations: LDLR: low-density lipoprotein receptor; apoB: apolipoprotein B; PKC: diacylglycerol-protein kinase C; MAPK: mitogen-activated protein kinase; ERK: p42/44 extracellular signal-regulated kinase; JNK: c-Jun N-terminal kinase; VLDLR: very low density lipoprotein receptor; PPARδ: peroxisome proliferator-activated receptor δ; SREBPs: sterol regulatory element-binding proteins; MTP: microsomal triacylglycerol transfer protein; LPDS: lipoprotein-deficient serum.
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Affiliation(s)
- Shizuka Kubota
- a Department of Applied Life Science, Faculty of Applied Biological Sciences , Gifu University , Gifu , Japan
| | - Yuma Tanaka
- a Department of Applied Life Science, Faculty of Applied Biological Sciences , Gifu University , Gifu , Japan
| | - Satoshi Nagaoka
- a Department of Applied Life Science, Faculty of Applied Biological Sciences , Gifu University , Gifu , Japan
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5
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Singla B, Lin HP, Ghoshal P, Cherian-Shaw M, Csányi G. PKCδ stimulates macropinocytosis via activation of SSH1-cofilin pathway. Cell Signal 2018; 53:111-121. [PMID: 30261270 DOI: 10.1016/j.cellsig.2018.09.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Revised: 09/19/2018] [Accepted: 09/23/2018] [Indexed: 12/13/2022]
Abstract
Macropinocytosis is an actin-dependent endocytic mechanism mediating internalization of extracellular fluid and associated solutes into cells. The present study was designed to identify the specific protein kinase C (PKC) isoform(s) and downstream effectors regulating actin dynamics during macropinocytosis. We utilized various cellular and molecular biology techniques, pharmacological inhibitors and genetically modified mice to study the signaling mechanisms mediating macropinocytosis in macrophages. The qRT-PCR experiments identified PKCδ as the predominant PKC isoform in macrophages. Scanning electron microscopy and flow cytometry analysis of FITC-dextran internalization demonstrated the functional role of PKCδ in phorbol ester- and hepatocyte growth factor (HGF)-induced macropinocytosis. Western blot analysis demonstrated that phorbol ester and HGF stimulate activation of slingshot phosphatase homolog 1 (SSH1) and induce cofilin Ser-3 dephosphorylation via PKCδ in macrophages. Silencing of SSH1 inhibited cofilin dephosphorylation and macropinocytosis stimulation. Interestingly, we also found that incubation of macrophages with BMS-5, a potent inhibitor of LIM kinase, does not stimulate macropinocytosis. In conclusion, the findings of the present study demonstrate a previously unidentified mechanism by which PKCδ via activation of SSH1 and cofilin dephosphorylation stimulates membrane ruffle formation and macropinocytosis. The results of the present study may contribute to a better understanding of the regulatory mechanisms during macrophage macropinocytosis.
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Affiliation(s)
- Bhupesh Singla
- Vascular Biology Center, 1460 Laney Walker Blvd., Augusta University, Medical College of Georgia, Augusta, GA 30912, USA
| | - Hui-Ping Lin
- Vascular Biology Center, 1460 Laney Walker Blvd., Augusta University, Medical College of Georgia, Augusta, GA 30912, USA
| | - Pushpankur Ghoshal
- Vascular Biology Center, 1460 Laney Walker Blvd., Augusta University, Medical College of Georgia, Augusta, GA 30912, USA
| | - Mary Cherian-Shaw
- Vascular Biology Center, 1460 Laney Walker Blvd., Augusta University, Medical College of Georgia, Augusta, GA 30912, USA
| | - Gábor Csányi
- Vascular Biology Center, 1460 Laney Walker Blvd., Augusta University, Medical College of Georgia, Augusta, GA 30912, USA; Department of Pharmacology and Toxicology, 1460 Laney Walker Blvd., Augusta University, Medical College of Georgia, Augusta, GA 30912, USA.
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6
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Nagiec MM, Duvall JR, Skepner AP, Howe EA, Bastien J, Comer E, Marie JC, Johnston SE, Negri J, Eichhorn M, Vantourout J, Clish C, Musunuru K, Foley M, Perez JR, Palmer MAJ. Novel tricyclic glycal-based TRIB1 inducers that reprogram LDL metabolism in hepatic cells. MEDCHEMCOMM 2018; 9:1831-1842. [PMID: 30542533 DOI: 10.1039/c8md00297e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 09/08/2018] [Indexed: 01/17/2023]
Abstract
Increased expression of the Tribbles pseudokinase 1 gene (TRIB1) is associated with lower plasma levels of LDL cholesterol and triglycerides, higher levels of HDL cholesterol and decreased risk of coronary artery disease and myocardial infarction. We identified a class of tricyclic glycal core-based compounds that upregulate TRIB1 expression in human HepG2 cells and phenocopy the effects of genetic TRIB1 overexpression as they inhibit expression of triglyceride synthesis genes and ApoB secretion in cells. In addition to predicted effects related to downregulation of VLDL assembly and secretion these compounds also have unexpected effects as they upregulate expression of LDLR and stimulate LDL uptake. This activity profile is unique and favorably differs from profiles produced by statins or other lipoprotein targeting therapies. BRD8518, the initial lead compound from the tricyclic glycal class, exhibited stereochemically dependent activity and the potency far exceeding previously described benzofuran BRD0418. Gene expression profiling of cells treated with BRD8518 demonstrated the anticipated changes in lipid metabolic genes and revealed a broad stimulation of early response genes. Consistently, we found that BRD8518 activity is MEK1/2 dependent and the treatment of HepG2 cells with BRD8518 stimulates ERK1/2 phosphorylation. In agreement with down-regulation of genes controlling triglyceride synthesis and assembly of lipoprotein particles, the mass spectrometry analysis of cell extracts showed reduced rate of incorporation of stable isotope labeled glycerol into triglycerides in BRD8518 treated cells. Furthermore, we describe medicinal chemistry efforts that led to identification of BRD8518 analogs with enhanced potency and pharmacokinetic properties suitable for in vivo studies.
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Affiliation(s)
- Marek M Nagiec
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Jeremy R Duvall
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Adam P Skepner
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Eleanor A Howe
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Jessica Bastien
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Eamon Comer
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Jean-Charles Marie
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Stephen E Johnston
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Joseph Negri
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Michelle Eichhorn
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Julien Vantourout
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Clary Clish
- Metabolite Profiling Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA
| | - Kiran Musunuru
- Department of Stem Cell and Regenerative Biology , Harvard University , Cambridge , MA 02138 , USA
| | - Michael Foley
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Jose R Perez
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
| | - Michelle A J Palmer
- Therapeutics Platform , Broad Institute of MIT and Harvard , Cambridge , MA02142 , USA . ; Tel: +1 617 714 7377
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7
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Taga M, Mouton-Liger F, Sadoune M, Gourmaud S, Norman J, Tible M, Thomasseau S, Paquet C, Nicoll JAR, Boche D, Hugon J. PKR modulates abnormal brain signaling in experimental obesity. PLoS One 2018; 13:e0196983. [PMID: 29795582 PMCID: PMC5968403 DOI: 10.1371/journal.pone.0196983] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 04/24/2018] [Indexed: 12/21/2022] Open
Abstract
Metabolic disorders including obesity and type 2 diabetes are known to be associated with chronic inflammation and are obvious risk factors for Alzheimer's disease. Recent evidences concerning obesity and diabetes suggest that the metabolic inflammasome ("metaflammasome") mediates chronic inflammation. The double-stranded RNA-dependent protein kinase (PKR) is a central component of the metaflammasome. In wild type (WT) and PKR-/- mice, blood glucose, insulin and lipid levels and the brain expression of the phosphorylated components of the metaflammasome-PKR, JNK, IRS1 and IKKbeta-were studied after the induction of obesity by a high fat diet (HFD). The results showed significant increased levels of activated brain metaflammasome proteins in exposed WT mice but the changes were not significant in PKR-/- mice. In addition, gain weight was observed in WT mice and also in PKR-/- mice exposed to HFD. Increased blood insulin level was more accentuated in PKR -/- mice. The modulation of PKR activity could be an appropriate therapeutic approach, aimed at reducing abnormal brain metabolism and inflammation linked to metabolic disorders in order to reduce the risk of neurodegeneration.
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Affiliation(s)
- Mariko Taga
- Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
- INSERM Units U942, Paris, France
| | | | | | | | - Jenny Norman
- Histochemistry Research Unit, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
| | | | | | - Claire Paquet
- INSERM Units U942, Paris, France
- Center of Cognitive Neurology Lariboisière Hospital, APHP, University Paris Diderot, Paris, France
| | - James A. R. Nicoll
- Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
- Department of Cellular Pathology, University Hospital Southampton NHS Foundation Trust, Southampton, Southampton, United Kingdom
| | - Delphine Boche
- Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
| | - Jacques Hugon
- INSERM Units U942, Paris, France
- Center of Cognitive Neurology Lariboisière Hospital, APHP, University Paris Diderot, Paris, France
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8
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Wang XJ, Qiao Y, Xiao MM, Wang L, Chen J, Lv W, Xu L, Li Y, Wang Y, Tan MD, Huang C, Li J, Zhao TC, Hou Z, Jing N, Chin YE. Opposing Roles of Acetylation and Phosphorylation in LIFR-Dependent Self-Renewal Growth Signaling in Mouse Embryonic Stem Cells. Cell Rep 2017; 18:933-946. [PMID: 28122243 DOI: 10.1016/j.celrep.2016.12.081] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 08/25/2016] [Accepted: 12/22/2016] [Indexed: 11/27/2022] Open
Abstract
LIF promotes self-renewal of mouse embryonic stem cells (mESCs), and in its absence, the cells differentiate. LIF binds to the LIF receptor (LIFR) and activates the JAK-STAT3 pathway, but it remains unknown how the receptor complex triggers differentiation or self-renewal. Here, we report that the LIFR cytoplasmic domain contains a self-renewal domain within the juxtamembrane region and a differentiation domain within the C-terminal region. The differentiation domain contains four SPXX repeats that are phosphorylated by MAPK to restrict STAT3 activation; the self-renewal domain is characterized by a 3K motif that is acetylated by p300. In mESCs, acetyl-LIFR undergoes homodimerization, leading to STAT3 hypo- or hyper-activation depending on the presence or absence of gp130. LIFR-activated STAT3 restricts differentiation via cytokine induction. Thus, LIFR acetylation and serine phosphorylation differentially promote stem cell self-renewal and differentiation.
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Affiliation(s)
- Xiong-Jun Wang
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai Jiao Tong University School of Medicine, 320 Yueyang Road, Shanghai 200031, China; Hongqiao Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yunbo Qiao
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China; iHuman Institute, Shanghai Tech University, 99 Haike Road, Shanghai 201210, China
| | - Minzhe M Xiao
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai Jiao Tong University School of Medicine, 320 Yueyang Road, Shanghai 200031, China
| | - Lingbo Wang
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Jun Chen
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China; Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Wenjian Lv
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Li Xu
- Department of Signal Transduction, School of Basic Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310053, China
| | - Yan Li
- Department of Signal Transduction, School of Basic Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310053, China
| | - Yumei Wang
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai Jiao Tong University School of Medicine, 320 Yueyang Road, Shanghai 200031, China
| | - Ming-Dian Tan
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai Jiao Tong University School of Medicine, 320 Yueyang Road, Shanghai 200031, China
| | - Chao Huang
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai Jiao Tong University School of Medicine, 320 Yueyang Road, Shanghai 200031, China
| | - Jinsong Li
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Ting C Zhao
- Department of Surgery, Boston University Medical School, Roger Williams Medical Center, Providence, RI 02908, USA
| | - Zhaoyuan Hou
- Hongqiao Institute of Medicine, Shanghai Tongren Hospital/Faculty of Basic Medicine, Shanghai Jiaotong University School of Medicine, Shanghai, China.
| | - Naihe Jing
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China.
| | - Y Eugene Chin
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai Jiao Tong University School of Medicine, 320 Yueyang Road, Shanghai 200031, China.
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9
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Mnasri N, Mamarbachi M, Allen BG, Mayer G. 5-Azacytidine engages an IRE1α-EGFR-ERK1/2 signaling pathway that stabilizes the LDL receptor mRNA. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2017; 1861:29-40. [PMID: 29208426 DOI: 10.1016/j.bbagrm.2017.11.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/09/2017] [Accepted: 11/29/2017] [Indexed: 01/06/2023]
Abstract
Hepatic low-density lipoprotein receptor (LDLR) is the primary conduit for the clearance of plasma LDL-cholesterol and increasing its expression represents a central goal for treating cardiovascular disease. However, LDLR mRNA is unstable and undergoes rapid turnover mainly due to the three AU-rich elements (ARE) in its proximal 3'-untranslated region (3'-UTR). Herein, our data revealed that 5-azacytidine (5-AzaC), an antimetabolite used in the treatment of myelodysplastic syndrome, stabilizes the LDLR mRNA through a previously unrecognized signaling pathway resulting in a strong increase of its protein level in human hepatocytes in culture. 5-AzaC caused a sustained activation of the inositol-requiring enzyme 1α (IRE1α) kinase domain and c-Jun N-terminal kinase (JNK) independently of endoplasmic reticulum stress. This resulted in activation of the epidermal growth factor receptor (EGFR) and extracellular signal-regulated kinase1/2 (ERK1/2) that, in turn, stabilized LDLR mRNA. Systematic mutation of the AREs (ARE1-3) in the LDLR 3'UTR and expression of each mutant coupled to a luciferase reporter in Huh7 cells demonstrated that ARE1 is required for rapid LDLR mRNA decay and 5-AzaC-induced mRNA stabilization via the IRE1α-EGFR-ERK1/2 signaling cascade. The characterization of this pathway will help to reveal potential targets to enhance plasma LDL clearance and novel cholesterol-lowering therapeutic strategies.
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Affiliation(s)
- Nourhen Mnasri
- Laboratory of Molecular and Cellular Biology, Montreal Heart Institute, Montréal, QC, Canada; Department of Biomedical Sciences, Université de Montréal, Montréal, QC, Canada
| | - Maya Mamarbachi
- Molecular Biology Core Facility, Montreal Heart Institute, Montréal, QC, Canada
| | - Bruce G Allen
- Laboratory of Cell Biology, Montreal Heart Institute, Montréal, QC, Canada; Department of Medicine, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada
| | - Gaétan Mayer
- Laboratory of Molecular and Cellular Biology, Montreal Heart Institute, Montréal, QC, Canada; Faculty of Pharmacy, Université de Montréal, Montréal, QC, Canada.
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10
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Lammi C, Zanoni C, Arnoldi A. IAVPGEVA, IAVPTGVA, and LPYP, three peptides from soy glycinin, modulate cholesterol metabolism in HepG2 cells through the activation of the LDLR-SREBP2 pathway. J Funct Foods 2015. [DOI: 10.1016/j.jff.2015.02.021] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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11
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Nagiec MM, Skepner AP, Negri J, Eichhorn M, Kuperwasser N, Comer E, Muncipinto G, Subramanian A, Clish C, Musunuru K, Duvall JR, Foley M, Perez JR, Palmer MAJ. Modulators of hepatic lipoprotein metabolism identified in a search for small-molecule inducers of tribbles pseudokinase 1 expression. PLoS One 2015; 10:e0120295. [PMID: 25811180 PMCID: PMC4374785 DOI: 10.1371/journal.pone.0120295] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 01/28/2015] [Indexed: 12/04/2022] Open
Abstract
Recent genome wide association studies have linked tribbles pseudokinase 1 (TRIB1) to the risk of coronary artery disease (CAD). Based on the observations that increased expression of TRIB1 reduces secretion of VLDL and is associated with lower plasma levels of LDL cholesterol and triglycerides, higher plasma levels of HDL cholesterol and reduced risk for myocardial infarction, we carried out a high throughput phenotypic screen based on quantitative RT-PCR assay to identify compounds that induce TRIB1 expression in human HepG2 hepatoma cells. In a screen of a collection of diversity-oriented synthesis (DOS)-derived compounds, we identified a series of benzofuran-based compounds that upregulate TRIB1 expression and phenocopy the effects of TRIB1 cDNA overexpression, as they inhibit triglyceride synthesis and apoB secretion in cells. In addition, the compounds downregulate expression of MTTP and APOC3, key components of the lipoprotein assembly pathway. However, CRISPR-Cas9 induced chromosomal disruption of the TRIB1 locus in HepG2 cells, while confirming its regulatory role in lipoprotein metabolism, demonstrated that the effects of benzofurans persist in TRIB1-null cells indicating that TRIB1 is sufficient but not necessary to transmit the effects of the drug. Remarkably, active benzofurans, as well as natural products capable of TRIB1 upregulation, also modulate hepatic cell cholesterol metabolism by elevating the expression of LDLR transcript and LDL receptor protein, while reducing the levels of PCSK9 transcript and secreted PCSK9 protein and stimulating LDL uptake. The effects of benzofurans are not masked by cholesterol depletion and are independent of the SREBP-2 regulatory circuit, indicating that these compounds represent a novel class of chemically tractable small-molecule modulators that shift cellular lipoprotein metabolism in HepG2 cells from lipogenesis to scavenging.
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Affiliation(s)
- Marek M. Nagiec
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Adam P. Skepner
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Joseph Negri
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Michelle Eichhorn
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Nicolas Kuperwasser
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Eamon Comer
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Giovanni Muncipinto
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Aravind Subramanian
- Cancer Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Clary Clish
- Metabolite Profiling Platform, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Kiran Musunuru
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Jeremy R. Duvall
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Michael Foley
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Jose R. Perez
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Michelle A. J. Palmer
- Therapeutics Platform, Center for the Science of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
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12
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Fan HC, Fernández-Hernando C, Lai JH. Protein kinase C isoforms in atherosclerosis: Pro- or anti-inflammatory? Biochem Pharmacol 2014; 88:139-49. [DOI: 10.1016/j.bcp.2014.01.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 01/06/2014] [Accepted: 01/07/2014] [Indexed: 12/12/2022]
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13
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Fryer LGD, Jones B, Duncan EJ, Hutchison CE, Ozkan T, Williams PA, Alder O, Nieuwdorp M, Townley AK, Mensenkamp AR, Stephens DJ, Dallinga-Thie GM, Shoulders CC. The endoplasmic reticulum coat protein II transport machinery coordinates cellular lipid secretion and cholesterol biosynthesis. J Biol Chem 2013; 289:4244-61. [PMID: 24338480 PMCID: PMC3924288 DOI: 10.1074/jbc.m113.479980] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Triglycerides and cholesterol are essential for life in most organisms. Triglycerides serve as the principal energy storage depot and, where vascular systems exist, as a means of energy transport. Cholesterol is essential for the functional integrity of all cellular membrane systems. The endoplasmic reticulum is the site of secretory lipoprotein production and de novo cholesterol synthesis, yet little is known about how these activities are coordinated with each other or with the activity of the COPII machinery, which transports endoplasmic reticulum cargo to the Golgi. The Sar1B component of this machinery is mutated in chylomicron retention disorder, indicating that this Sar1 isoform secures delivery of dietary lipids into the circulation. However, it is not known why some patients with chylomicron retention disorder develop hepatic steatosis, despite impaired intestinal fat malabsorption, and why very severe hypocholesterolemia develops in this condition. Here, we show that Sar1B also promotes hepatic apolipoprotein (apo) B lipoprotein secretion and that this promoting activity is coordinated with the processes regulating apoB expression and the transfer of triglycerides/cholesterol moieties onto this large lipid transport protein. We also show that although Sar1A antagonizes the lipoprotein secretion-promoting activity of Sar1B, both isoforms modulate the expression of genes encoding cholesterol biosynthetic enzymes and the synthesis of cholesterol de novo. These results not only establish that Sar1B promotes the secretion of hepatic lipids but also adds regulation of cholesterol synthesis to Sar1B's repertoire of transport functions.
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Affiliation(s)
- Lee G D Fryer
- From the Endocrinology Centre, William Harvey Research Institute, Queen Mary University of London and Barts and The London School of Medicine and Dentistry, Charterhouse Square, London EC1M 6BQ, United Kingdom
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14
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Yashiro T, Nanmoku M, Shimizu M, Inoue J, Sato R. 5-Aminoimidazole-4-carboxamide ribonucleoside stabilizes low density lipoprotein receptor mRNA in hepatocytes via ERK-dependent HuR binding to an AU-rich element. Atherosclerosis 2013; 226:95-101. [DOI: 10.1016/j.atherosclerosis.2012.09.033] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2012] [Revised: 08/23/2012] [Accepted: 09/24/2012] [Indexed: 10/27/2022]
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15
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Epigallocatechin gallate changes mRNA expression level of genes involved in cholesterol metabolism in hepatocytes. Br J Nutr 2011; 107:769-73. [DOI: 10.1017/s0007114511003758] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Catechins, compounds derived from green tea, have been shown to improve cholesterol metabolism in animal studies, but the molecular mechanisms underlying this function have not been fully understood. We performed DNA microarray analysis in order to clarify the effects of epigallocatechin gallate (EGCG), the dominant catechin in green tea, on cholesterol metabolism in HepG2 hepatocytes. This revealed that the expression levels of several genes related to cholesterol metabolism, including the LDL receptor, were changed by EGCG treatment. Using a real-time PCR technique, we confirmed that EGCG treatment up-regulated mRNA expression level of the LDL receptor. Moreover, EGCG decreased extracellular apoB levels. These findings indicated that EGCG improves cholesterol metabolism through the up-regulation of LDL receptor and also reduces extracellular apoB levels.
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16
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Yashiro T, Yokoi Y, Shimizu M, Inoue J, Sato R. Chenodeoxycholic acid stabilization of LDL receptor mRNA depends on 3'-untranslated region and AU-rich element-binding protein. Biochem Biophys Res Commun 2011; 409:155-9. [PMID: 21473855 DOI: 10.1016/j.bbrc.2011.04.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Accepted: 04/01/2011] [Indexed: 10/18/2022]
Abstract
Human low-density lipoprotein receptor (LDLR) mRNA is unstable and contains four AU-rich elements (AREs) in the 3'-untranslated region (3'-UTR). The aim of this study was to verify the involvement of the 3'-UTR in the rapid degradation of LDLR mRNA. This study revealed that the 3'-UTR is necessary and sufficient for the degradation, and that the 1st ARE (ARE1) close to the stop codon associates with cytoplasmic proteins, and is primarily responsible for the degradation. Chenodeoxycholic acid (CDCA) treatment stabilized chimeric GFP-LDLR 3'-UTR mRNA and accompanied mitogen-activated protein kinase (MAPK) activation. The UV cross-linking assays showed that a protein of 80kDa increasingly binds to the region including the ARE1 in response to CDCA-mediated MAPK activation.
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Affiliation(s)
- Takuya Yashiro
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
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17
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Moraes KCM. RNA surveillance: molecular approaches in transcript quality control and their implications in clinical diseases. Mol Med 2010; 16:53-68. [PMID: 19829759 PMCID: PMC2761007 DOI: 10.2119/molmed.2009.00026] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2009] [Accepted: 10/06/2009] [Indexed: 11/06/2022] Open
Abstract
Production of mature mRNAs that encode functional proteins involves highly complex pathways of synthesis, processing and surveillance. At numerous steps during the maturation process, the mRNA transcript undergoes scrutiny by cellular quality control machinery. This extensive RNA surveillance ensures that only correctly processed mature mRNAs are translated and precludes production of aberrant transcripts that could encode mutant or possibly deleterious proteins. Recent advances in elucidating the molecular mechanisms of mRNA processing have demonstrated the existence of an integrated network of events, and have revealed that a variety of human diseases are caused by disturbances in the well-coordinated molecular equilibrium of these events. From a medical perspective, both loss and gain of function are relevant, and a considerable number of different diseases exemplify the importance of the mechanistic function of RNA surveillance in a cell. Here, mechanistic hallmarks of mRNA processing steps are reviewed, highlighting the medical relevance of their deregulation and how the understanding of such mechanisms can contribute to the development of therapeutic strategies.
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Affiliation(s)
- Karen C M Moraes
- Molecular Biology Laboratory, IP&D, Universidade do Vale do Paraíba, São José dos Campos, São Paulo, CEP-12244-000, Brazil.
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18
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Lorin S, Borges A, Ribeiro Dos Santos L, Souquère S, Pierron G, Ryan KM, Codogno P, Djavaheri-Mergny M. c-Jun NH2-terminal kinase activation is essential for DRAM-dependent induction of autophagy and apoptosis in 2-methoxyestradiol-treated Ewing sarcoma cells. Cancer Res 2009; 69:6924-31. [PMID: 19706754 DOI: 10.1158/0008-5472.can-09-1270] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ewing sarcoma and osteosarcoma are two aggressive cancers that affect bones and soft tissues in children and adolescents. Despite multimodal therapy, patients with metastatic sarcoma have a poor prognosis, emphasizing a need for more effective treatment. We have shown previously that 2-methoxyestradiol (2-ME), an antitumoral compound, induces apoptosis in Ewing sarcoma cells through c-Jun NH(2)-terminal kinase (JNK) activation. In the present study, we provide evidence that 2-ME elicits macroautophagy, a process that participates in apoptotic responses, in a JNK-dependent manner, in Ewing sarcoma and osteosarcoma cells. We also found that the enhanced activation of JNK by 2-ME is partially regulated by p53, highlighting the relationship of JNK and autophagy to p53 signaling pathway. Furthermore, we showed that 2-ME up-regulates damage-regulated autophagy modulator (DRAM), a p53 target gene, in Ewing sarcoma cells through a mechanism that involves JNK activation. The silencing of DRAM expression reduced both apoptosis and autophagy triggered by 2-ME in Ewing sarcoma and osteosarcoma cells. Our results therefore identify JNK as a novel mediator of DRAM regulation. These findings suggest that 2-ME or other anticancer therapies that increase DRAM expression or function could be used to effectively treat sarcoma patients.
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Affiliation(s)
- Séverine Lorin
- Institut National de la Santé et de la Recherche Médicale U756, Faculté de Pharmacie, Université Paris-Sud 11, Châtenay-Malabry, France
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