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Cortés-López M, Chamely P, Hawkins AG, Stanley RF, Swett AD, Ganesan S, Mouhieddine TH, Dai X, Kluegel L, Chen C, Batta K, Furer N, Vedula RS, Beaulaurier J, Drong AW, Hickey S, Dusaj N, Mullokandov G, Stasiw AM, Su J, Chaligné R, Juul S, Harrington E, Knowles DA, Potenski CJ, Wiseman DH, Tanay A, Shlush L, Lindsley RC, Ghobrial IM, Taylor J, Abdel-Wahab O, Gaiti F, Landau DA. Single-cell multi-omics defines the cell-type-specific impact of splicing aberrations in human hematopoietic clonal outgrowths. Cell Stem Cell 2023; 30:1262-1281.e8. [PMID: 37582363 PMCID: PMC10528176 DOI: 10.1016/j.stem.2023.07.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 05/28/2023] [Accepted: 07/18/2023] [Indexed: 08/17/2023]
Abstract
RNA splicing factors are recurrently mutated in clonal blood disorders, but the impact of dysregulated splicing in hematopoiesis remains unclear. To overcome technical limitations, we integrated genotyping of transcriptomes (GoT) with long-read single-cell transcriptomics and proteogenomics for single-cell profiling of transcriptomes, surface proteins, somatic mutations, and RNA splicing (GoT-Splice). We applied GoT-Splice to hematopoietic progenitors from myelodysplastic syndrome (MDS) patients with mutations in the core splicing factor SF3B1. SF3B1mut cells were enriched in the megakaryocytic-erythroid lineage, with expansion of SF3B1mut erythroid progenitor cells. We uncovered distinct cryptic 3' splice site usage in different progenitor populations and stage-specific aberrant splicing during erythroid differentiation. Profiling SF3B1-mutated clonal hematopoiesis samples revealed that erythroid bias and cell-type-specific cryptic 3' splice site usage in SF3B1mut cells precede overt MDS. Collectively, GoT-Splice defines the cell-type-specific impact of somatic mutations on RNA splicing, from early clonal outgrowths to overt neoplasia, directly in human samples.
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Affiliation(s)
- Mariela Cortés-López
- New York Genome Center, New York, NY, USA; Division of Hematology and Medical Oncology, Department of Medicine and Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA
| | - Paulina Chamely
- New York Genome Center, New York, NY, USA; Division of Hematology and Medical Oncology, Department of Medicine and Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA
| | - Allegra G Hawkins
- Childhood Cancer Data Lab, Alex's Lemonade Stand Foundation, Philadelphia, PA, USA
| | - Robert F Stanley
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Ariel D Swett
- New York Genome Center, New York, NY, USA; Division of Hematology and Medical Oncology, Department of Medicine and Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA
| | - Saravanan Ganesan
- New York Genome Center, New York, NY, USA; Division of Hematology and Medical Oncology, Department of Medicine and Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA
| | - Tarek H Mouhieddine
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Xiaoguang Dai
- Oxford Nanopore Technologies Inc., New York, NY, USA
| | - Lloyd Kluegel
- New York Genome Center, New York, NY, USA; Division of Hematology and Medical Oncology, Department of Medicine and Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA
| | - Celine Chen
- New York Genome Center, New York, NY, USA; Division of Hematology and Medical Oncology, Department of Medicine and Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA; Tri-Institutional MD-PhD Program, Weill Cornell Medicine, Rockefeller University, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Kiran Batta
- Division of Cancer Sciences, The University of Manchester, Manchester, UK
| | - Nili Furer
- Weizmann Institute of Science, Department of Molecular Cell Biology, Rehovot, Israel
| | - Rahul S Vedula
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | | | | | - Scott Hickey
- Oxford Nanopore Technologies Inc., San Francisco, CA, USA
| | - Neville Dusaj
- New York Genome Center, New York, NY, USA; Division of Hematology and Medical Oncology, Department of Medicine and Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA; Tri-Institutional MD-PhD Program, Weill Cornell Medicine, Rockefeller University, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Gavriel Mullokandov
- New York Genome Center, New York, NY, USA; Division of Hematology and Medical Oncology, Department of Medicine and Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA
| | - Adam M Stasiw
- New York Genome Center, New York, NY, USA; Division of Hematology and Medical Oncology, Department of Medicine and Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA
| | - Jiayu Su
- New York Genome Center, New York, NY, USA; Department of Systems Biology, Columbia University, New York, NY, USA
| | - Ronan Chaligné
- Computational and Systems Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Sissel Juul
- Oxford Nanopore Technologies Inc., New York, NY, USA
| | | | - David A Knowles
- New York Genome Center, New York, NY, USA; Department of Systems Biology, Columbia University, New York, NY, USA; Department of Computer Science, Columbia University, New York, NY, USA
| | - Catherine J Potenski
- New York Genome Center, New York, NY, USA; Division of Hematology and Medical Oncology, Department of Medicine and Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA
| | - Daniel H Wiseman
- Division of Cancer Sciences, The University of Manchester, Manchester, UK
| | - Amos Tanay
- Weizmann Institute of Science, Department of Computer Science and Applied Mathematics, Rehovot, Israel
| | - Liran Shlush
- Weizmann Institute of Science, Department of Molecular Cell Biology, Rehovot, Israel
| | - Robert C Lindsley
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Irene M Ghobrial
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Justin Taylor
- Sylvester Comprehensive Cancer Center, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Omar Abdel-Wahab
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Federico Gaiti
- University Health Network, Princess Margaret Cancer Centre, Toronto, ON, Canada; University of Toronto, Medical Biophysics, Toronto, ON, Canada.
| | - Dan A Landau
- New York Genome Center, New York, NY, USA; Division of Hematology and Medical Oncology, Department of Medicine and Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA; Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, USA.
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Yu X, Huang Y, Li Y, Li T, Yan S, Ai X, Lv X, Fan L, Xie J. Mycobacterium tuberculosis PE_PGRS1 promotes mycobacteria intracellular survival via reducing the concentration of intracellular free Ca 2+ and suppressing endoplasmic reticulum stress. Mol Immunol 2023; 154:24-32. [PMID: 36584479 DOI: 10.1016/j.molimm.2022.12.007] [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: 08/19/2022] [Revised: 11/03/2022] [Accepted: 12/13/2022] [Indexed: 12/29/2022]
Abstract
Mycobacterium tuberculosis (M. tuberculosis) is the causative agent of tuberculosis (TB). And the PE_PGRS family members of M. tuberculosis are closely associated with virulence and antigen presentation but with function largely elusive. PE_PGRS1(Rv0109) contained 7 Ca2+ binding domains of GGXGXD/NXUX (X is any amino acid), which can reduce intracellular Ca2+ surge. In addition, PE_PGRS1 can mitigate the activation of PERK branch in endoplasmic reticulum (ER) stress by down-regulating the expression of CHOP, Bip, p-PERK, p-eIF2α, and ATF4. Interestingly, we found that two splicing variations of Bax/Bcl-2, Baxβ, and Bcl-2α, were differentially expressed after infection with Ms_PE_PGRS1, and may be involved in the regulation of apoptosis. Hence, this study identified that PE_PGRS1 is a novel calcium-associated protein that can decrease intracellular Ca2+ levels and the PERK axis. And the weakening of the PERK-eIF2α-ATF4 axis reduces THP-1 macrophages apoptosis, promotes the survival of mycobacteria in macrophages.
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Affiliation(s)
- Xi Yu
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Yu Huang
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Yuzhu Li
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Tongxin Li
- Chongqing Public Health Medical Center, Southwest University Public Health Hospital, central laboratory, Chongqing 400715, China
| | - Shuangquan Yan
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Xuefeng Ai
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Xi Lv
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Lin Fan
- Shanghai Clinic and Research Center of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai Key Laboratory of Tuberculosis, Shanghai 200433, China.
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China.
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Aghaei M, KhanAhmad H, Aghaei S, Ali Nilforoushzadeh M, Mohaghegh MA, Hejazi SH. The role of Bax in the apoptosis of Leishmania-infected macrophages. Microb Pathog 2019; 139:103892. [PMID: 31778755 DOI: 10.1016/j.micpath.2019.103892] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 10/30/2019] [Accepted: 11/23/2019] [Indexed: 12/18/2022]
Abstract
BACKGROUND Leishmania is a protozoan parasite that nests in macrophages and is responsible for the Leishmaniasis disease. In spite of different defense pathways, last strategy of macrophage for killing parasite is apoptosis process. By permeableizing the mitochondrial outer membrane (MOM). As breaching MOM releases apoptogenic factors like cytochrome-c which activate caspases that result in the destruction of the cell. In this review, we summarized the appropriate manuscripts regarding the bax includes, its different types and the effect of bax on the apoptosis of Leishmania and parasite-infected macrophages. METHODS Information about the role of BAX in the apoptosis of parasite-infected macrophage of recent articles were surveyed by searching computerized bibliographic database PubMed and Google Scholar entering the keywords BAX and leishmaniasis. RESULTS The common studies revealed Leishmania use different survival strategies for inhibiting macrophage apoptosis. As Leishmania by preventing homooligomerization or upregulating the anti-apoptotic molecule Bcl-2 can prohibits proteins of host-cell apoptosis such as Bax that is required for mitochondrial permeabilisation during apoptosis. CONCLUSION With regard to the supportive role of bax in apoptosis and the preventive role of Leishmania in its function, it seems that expression of bax gene in parasite by technologies like transgenic or down regulating of anti-apoptotic molecule Bcl-2 by miRNA could be prompted the apoptosis process of infected-macrophages and inhibited extensive spread of Leishmania and the resulting lesions.
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Affiliation(s)
- Maryam Aghaei
- Skin Diseases and Leishmaniasis Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hossein KhanAhmad
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Shahrzad Aghaei
- Cellular and Molecular Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | | | - Mohammad-Ali Mohaghegh
- Department of Laboratory Sciences, School of Paramedical Sciences, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran; Health Sciences Research Center, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran
| | - Seyed Hossein Hejazi
- Skin Diseases and Leishmaniasis Research Center, Isfahan University of Medical Sciences, Isfahan, Iran; Skin Disease and Leishmaniasis Research Center, Department of Parasitology and Mycology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
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Evaluation of Bax and Bak gene mutations and expression in breast cancer. BIOMED RESEARCH INTERNATIONAL 2014; 2014:249372. [PMID: 24672785 PMCID: PMC3933335 DOI: 10.1155/2014/249372] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2013] [Accepted: 11/11/2013] [Indexed: 02/07/2023]
Abstract
Genetic analyses have provided evidence to suggest that Bax and Bak are the essential genes for apoptosis in mammalians cells. This study aimed to search for biomarkers in breast cancer to be used as prognostic markers for the disease. The Bak and Bax genes expressions were analyzed in 23 breast cancer patients by RT-PCR technique. SSCP technique was used to detect the mobility of the abnormal fragment in Bak exon 4. PCR for Bax promoter was digested with Tau 1 restriction enzyme to identify a single polymorphism G(-248)A. The expression of Bak gene is related to several clinical factors of breast cancer. The analysis of Bax RNA showed 4 isoforms of Bax with different distributions in the normal and tumor tissues. These isoforms were Bax α, d, δ, and ζ. Exon 4 had a normal pattern in all cases of breast cancer. There was a statistically significant difference in the frequency distribution of the G(-248)A genotypes in the breast cancer tissues with grade 3+high, T2 stage, lobular +other, and PR −ve subgroups. In this study, Bak expression seems to lead to development of breast cancer and affects the disease progression. Also, Bax d and Bax δ could be used as risk factor and biomarker for breast cancer with the distribution of G284A.
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Mechanisms of toxicity by proinflammatory cytokines in a novel human pancreatic beta cell line, 1.1B4. Biochim Biophys Acta Gen Subj 2013; 1840:136-45. [PMID: 24005237 DOI: 10.1016/j.bbagen.2013.08.022] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 08/07/2013] [Accepted: 08/26/2013] [Indexed: 12/17/2022]
Abstract
BACKGROUND Molecular mechanisms of toxicity and cell damage were investigated in the novel human beta cell line, 1.1B4, after exposure to proinflammatory cytokines - IL-1β, IFN-γ, TNF-α. METHODS MTT assay, insulin radioimmunoassay, glucokinase assay, real time reverse transcription PCR, western blotting, nitrite assay, caspase assay and comet assay were used to investigate mechanisms of cytokine toxicity. RESULTS Viability of 1.1B4 cells decreased after 18h cytokine exposure. Cytokines significantly reduced cellular insulin content and impaired insulin secretion induced by glucose, alanine, KCl, elevated Ca(2+), GLP-1 or forskolin. Glucokinase enzyme activity, regulation of intracellular Ca(2+) and PDX1 protein expression were significantly reduced by cytokines. mRNA expression of genes involved in secretory function - INS, GCK, PCSK2 and GJA1 was downregulated in cytokine treated 1.1B4 cells. Upregulation of transcription of genes involved in antioxidant defence - SOD2 and GPX1 was observed, suggesting involvement of oxidative stress. Cytokines also upregulated transcriptions of NFKB1 and STAT1, which was accompanied by a significant increase in NOS2 transcription and accumulation of nitrite in culture medium, implicating nitrosative stress. Oxidative and nitrosative stresses induced apoptosis was evident from increased % tail DNA, DNA fragmentation, caspase 3/7 activity, apoptotic cells and lower BCL2 protein expression. CONCLUSIONS This study delineates molecular mechanisms of cytokine toxicity in 1.1B4 cells, which agree with earlier observations using human islets and rodent beta cells. GENERAL SIGNIFICANCE This study emphasizes the potential usefulness of this cell line as a human beta cell model for research investigating autoimmune destruction of pancreatic beta cells.
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Zhang Z, Ding Y, Dai X, Wang J, Li Y. Epigallocatechin-3-gallate protects pro-inflammatory cytokine induced injuries in insulin-producing cells through the mitochondrial pathway. Eur J Pharmacol 2011; 670:311-6. [DOI: 10.1016/j.ejphar.2011.08.033] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2011] [Revised: 08/11/2011] [Accepted: 08/27/2011] [Indexed: 10/17/2022]
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Cantley J, Boslem E, Laybutt DR, Cordery DV, Pearson G, Carpenter L, Leitges M, Biden TJ. Deletion of protein kinase Cδ in mice modulates stability of inflammatory genes and protects against cytokine-stimulated beta cell death in vitro and in vivo. Diabetologia 2011; 54:380-9. [PMID: 21103982 DOI: 10.1007/s00125-010-1962-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2010] [Accepted: 10/06/2010] [Indexed: 12/23/2022]
Abstract
AIMS/HYPOTHESIS Proinflammatory cytokines contribute to beta cell destruction in type 1 diabetes, but the mechanisms are incompletely understood. The aim of the current study was to address the role of the protein kinase C (PKC) isoform PKCδ, a diverse regulator of cell death, in cytokine-stimulated apoptosis in primary beta cells. METHODS Islets isolated from wild-type or Prkcd(-/-) mice were treated with IL-1β, TNF-α and IFNγ and assayed for apoptosis, nitric oxide (NO) generation and insulin secretion. Activation of signalling pathways, apoptosis and endoplasmic reticulum (ER) stress were determined by immunoblotting. Stabilisation of mRNA transcripts was measured by RT-PCR following transcriptional arrest. Mice were injected with multiple low doses of streptozotocin (MLD-STZ) and fasting blood glucose monitored. RESULTS Deletion of Prkcd inhibited apoptosis and NO generation in islets stimulated ex vivo with cytokines. It also delayed the onset of hyperglycaemia in MLD-STZ-treated mice. Activation of ERK, p38, JNK, AKT1, the ER stress markers DDIT3 and phospho-EIF2α and the intrinsic apoptotic markers BCL2 and MCL1 was not different between genotypes. However, deletion of Prkcd destabilised mRNA transcripts for Nos2, and for multiple components of the toll-like receptor 2 (TLR2) signalling complex, which resulted in disrupted TLR2 signalling. CONCLUSIONS/INTERPRETATION Loss of PKCδ partially protects against hyperglycaemia in the MLD-STZ model in vivo, and against cytokine-mediated apoptosis in vitro. This is accompanied by reduced NO generation and destabilisation of Nos2 and components of the TLR2 signalling pathway. The results highlight a mechanism for regulating proinflammatory gene expression in beta cells independently of transcription.
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Affiliation(s)
- J Cantley
- Garvan Institute of Medical Research, St Vincent's Hospital, 384 Victoria Street, Darlinghurst, Sydney, NSW 2010, Australia
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Mehmeti I, Lenzen S, Lortz S. Modulation of Bcl-2-related protein expression in pancreatic beta cells by pro-inflammatory cytokines and its dependence on the antioxidative defense status. Mol Cell Endocrinol 2011; 332:88-96. [PMID: 20933054 DOI: 10.1016/j.mce.2010.09.017] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2010] [Revised: 09/03/2010] [Accepted: 09/28/2010] [Indexed: 12/27/2022]
Abstract
Pro-inflammatory cytokines are key mediators in the selective and progressive destruction of insulin-producing beta cells during type 1 diabetes development. However, the mechanisms of cytokine-induced beta cell apoptosis are not fully understood. This study demonstrates that pro-inflammatory cytokines strongly modified the expression of the anti-apoptotic protein Bcl-2 and the pro-apoptotic BH3-only proteins Bad, Bim, and Bid in primary rat islets and insulin-producing RINm5F cells. Overexpression of mitochondrially located catalase (MitoCatalase) specifically increased basal Bcl-2 and decreased basal Bax expression, suppressed cytokine-mediated reduction of Bcl-2, and thereby prevented the release of cytochrome c, Smac/DIABLO and the activation of caspase-9 and -3. Thus, cytokine-mediated decrease of Bcl-2 expression and the sequentially changed Bax/Bcl-2 ratio are responsible for the release of pro-apoptotic mitochondrial factors, activation of caspase-9, and ultimately caspase-3. These results indicate that activation of the intrinsic/mitochondrial apoptosis pathway is essential for cytokine-induced beta cell death and the mitochondrial generation of reactive oxygen species, in particular mitochondrial hydrogen peroxide, differentially regulates the Bax/Bcl-2 ratio.
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Affiliation(s)
- Ilir Mehmeti
- Institute of Clinical Biochemistry, Hannover Medical School, 30623 Hannover, Germany
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Joly E, Roduit R, Peyot ML, Habinowski SA, Ruderman NB, Witters LA, Prentki M. Glucose represses PPARα gene expression via AMP-activated protein kinase but not via p38 mitogen-activated protein kinase in the pancreatic β-cell. J Diabetes 2009; 1:263-72. [PMID: 20923527 DOI: 10.1111/j.1753-0407.2009.00043.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Peroxisome proliferator-activated receptor α (PPARα) regulates the expression of fatty acid metabolism genes and is thought to play a role in the regulation of insulin secretion and lipid detoxification. We have examined the mechanism whereby glucose decreases PPARα gene expression in the pancreatic β-cell. METHODS INS832/13 β-cell and isolated rat islets were incubated at 3 and 20 mM glucose for 18 h in the absence or presence of adenosine monophosphate (AMP)-activated protein kinase (AMPK) activators and inhibitors, as well as p38 mitogen-activated protein kinase (p38 MAPK) inhibitors. In another set of experiments, INS832/13 were infected with an adenovirus expressing a dominant-negative form of AMPK. PPARα expression levels were measured by reverse transcription polymerase chain reaction and Western blot. RESULTS Elevated glucose reduced the abundance of the PPARα transcript and protein, and its target genes acyl-coenzyme A (CoA) oxidase (ACO) and uncoupling protein 2 (UCP-2) in INS832/13 β-cell and isolated rat islets. Glucose reduced AMPK activity, while the AMPK activators 5-amino-4-imidazolecarboxamide riboside and metformin increased PPARα expression and suppressed the action of glucose. By contrast, the AMPK inhibitor compound C mimicked the glucose effect. A dominant negative form of AMPKα reduced the PPARα, ACO and UCP-2 transcripts to the same extent as elevated glucose. Pharmacological evidence indicated that glucose-regulated PPARα expression does not involve p38 MAPK, a target of AMPK in several cell types. CONCLUSIONS The results indicate that glucose represses PPARα gene expression via AMPK, but not via p38 MAPK in the β-cell.
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Affiliation(s)
- Erik Joly
- Montreal Diabetes Research Center and CRCHUM, Montréal, Québec, Canada.
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Egefjord L, Jensen JL, Bang-Berthelsen CH, Petersen AB, Smidt K, Schmitz O, Karlsen AE, Pociot F, Chimienti F, Rungby J, Magnusson NE. Zinc transporter gene expression is regulated by pro-inflammatory cytokines: a potential role for zinc transporters in beta-cell apoptosis? BMC Endocr Disord 2009; 9:7. [PMID: 19243577 PMCID: PMC2651882 DOI: 10.1186/1472-6823-9-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Accepted: 02/25/2009] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Beta-cells are extremely rich in zinc and zinc homeostasis is regulated by zinc transporter proteins. beta-cells are sensitive to cytokines, interleukin-1beta (IL-1beta) has been associated with beta-cell dysfunction and -death in both type 1 and type 2 diabetes. This study explores the regulation of zinc transporters following cytokine exposure. METHODS The effects of cytokines IL-1beta, interferon-gamma (IFN-gamma), and tumor necrosis factor-alpha (TNF-alpha) on zinc transporter gene expression were measured in INS-1-cells and rat pancreatic islets. Being the more sensitive transporter, we further explored ZnT8 (Slc30A8): the effect of ZnT8 over expression on cytokine induced apoptosis was investigated as well as expression of the insulin gene and two apoptosis associated genes, BAX and BCL2. RESULTS Our results showed a dynamic response of genes responsible for beta-cell zinc homeostasis to cytokines: IL-1beta down regulated a number of zinc-transporters, most strikingly ZnT8 in both islets and INS-1 cells. The effect was even more pronounced when mixing the cytokines. TNF-alpha had little effect on zinc transporter expression. IFN-gamma down regulated a number of zinc transporters. Insulin expression was down regulated by all cytokines. ZnT8 over expressing cells were more sensitive to IL-1beta induced apoptosis whereas no differences were observed with IFN-gamma, TNF-alpha, or a mixture of cytokines. CONCLUSION The zinc transporting system in beta-cells is influenced by the exposure to cytokines. Particularly ZnT8, which has been associated with the development of diabetes, seems to be cytokine sensitive.
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Affiliation(s)
- Lærke Egefjord
- Department of Pharmacology, University of Aarhus, Aarhus, Denmark
| | - Jens Ledet Jensen
- Department of Theoretical Statistics Department of Mathematical Sciences, University of Aarhus, Aarhus, Denmark
| | | | | | - Kamille Smidt
- Department of Pharmacology, University of Aarhus, Aarhus, Denmark
| | - Ole Schmitz
- Department of Pharmacology, University of Aarhus, Aarhus, Denmark
| | | | | | | | - Jørgen Rungby
- Department of Pharmacology, University of Aarhus, Aarhus, Denmark
| | - Nils E Magnusson
- Department of Pharmacology, University of Aarhus, Aarhus, Denmark
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Biphasic effect of insulin on beta cell apoptosis depending on glucose deprivation. FEBS Lett 2008; 582:3855-60. [DOI: 10.1016/j.febslet.2008.10.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Revised: 10/06/2008] [Accepted: 10/13/2008] [Indexed: 01/09/2023]
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12
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Zaitseva II, Sharoyko V, Størling J, Efendic S, Guerin C, Mandrup-Poulsen T, Nicotera P, Berggren PO, Zaitsev SV. RX871024 reduces NO production but does not protect against pancreatic beta-cell death induced by proinflammatory cytokines. Biochem Biophys Res Commun 2006; 347:1121-8. [PMID: 16870144 DOI: 10.1016/j.bbrc.2006.06.197] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2006] [Accepted: 06/30/2006] [Indexed: 11/19/2022]
Abstract
The imidazoline compound RX871024 reduces IL-1beta-induced NO production thereby protecting against IL-1beta-induced beta-cell apoptosis. The aim of this study was to evaluate whether imidazolines RX871024 and efaroxan protect beta-cells against death in the presence of a combination of the cytokines IL-1beta, IFNgamma, and TNFalpha. To address this issue, experiments involving different methods for detection of cell death, different concentrations of the cytokines, and a variety of conditions of preparation and culturing of ob/ob mouse islets and beta-cells have been carried out. Thoroughly performed experiments have not been able to demonstrate a protective effect of RX871024 and efaroxan on beta-cell death induced by the combination of cytokines. However, the inhibitory effect of RX871024 on NO production in ob/ob mouse islets and beta-cells was still observed in the presence of all three cytokines and correlated with the decrease in p38 MAPK phosphorylation. Conversely, efaroxan did not affect cytokine-induced NO production. Our data indicate that a combination of pro-inflammatory cytokines IL-1beta, IFNgamma, and TNFalpha, conditions modelling those that take place in type 1 diabetes, induces pancreatic beta-cell death that does not directly correlate with NO production and cannot be counteracted with imidazoline compounds.
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Affiliation(s)
- Irina I Zaitseva
- The Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76 Stockholm, Sweden
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13
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Martens GA, Cai Y, Hinke S, Stangé G, Van de Casteele M, Pipeleers D. Glucose suppresses superoxide generation in metabolically responsive pancreatic beta cells. J Biol Chem 2005; 280:20389-96. [PMID: 15774474 DOI: 10.1074/jbc.m411869200] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
High rates of glucose metabolism and mitochondrial electron transport have been associated with increased mitochondrial production of reactive oxygen species (ROS). This mechanism was also proposed as a possible cause for dysfunction and death of pancreatic beta cells exposed to high glucose levels. We examined whether high rates of glucose metabolism increase ROS production in purified rat beta cells. Glucose up to 20 mm did not stimulate H(2)O(2) or superoxide production, whereas it dose-dependently increased cellular NAD(P)H and FADH(2) levels with an EC(50) around 8 mm. On the contrary, glucose concentration-dependently suppressed H(2)O(2) and superoxide formation, with a major effect between 0 and 5 mm, parallel to an increase in cellular NAD(P)H levels. This suppressive effect was more marked in beta cells with higher NAD(P)H responsiveness to glucose; it was not observed in glucagon-containing alpha cells, which lacked a glucose-induced increase in NAD(P)H. Suppression was also induced by the mitochondrial substrates leucine and succinate. Experiments with electron transport chain inhibitors indicate a role of respiratory complex I in ROS production at low mitochondrial activity and low NADH levels. Superoxide production at low glucose is potentially cytotoxic, because scavenging by the superoxide dismutase mimetic agent manganese(III)tetrakis(4-benzoic acid)porphyrin was found to reduce the rate of beta cell apoptosis. Analysis of islets cultured at 20 mm glucose confirmed that this condition does not induce ROS production in beta cells as a result of their increased rates of glucose metabolism. Our study indicates the need of beta cells for basal nutrients maintaining mitochondrial NADH production at levels that suppress ROS accumulation from an inadequate respiratory complex I activity and thus inhibit a potential apoptotic pathway.
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Affiliation(s)
- Geert A Martens
- Diabetes Research Center, Brussels Free University-VUB, Laarbeeklaan 103, B-1090 Brussels, Belgium
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14
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Kefas BA, Cai Y, Kerckhofs K, Ling Z, Martens G, Heimberg H, Pipeleers D, Van de Casteele M. Metformin-induced stimulation of AMP-activated protein kinase in beta-cells impairs their glucose responsiveness and can lead to apoptosis. Biochem Pharmacol 2004; 68:409-16. [PMID: 15242807 DOI: 10.1016/j.bcp.2004.04.003] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2004] [Accepted: 04/15/2004] [Indexed: 01/04/2023]
Abstract
Metformin is an anti-diabetic drug that increases glucose utilization in insulin-sensitive tissues. The effect is in part attributable to a stimulation of AMP-activated protein kinase (AMPK). The present study demonstrates that metformin (0.5-2mM) also dose-dependently activates AMPK in insulin-producing MIN6 cells and in primary rat beta-cells, leading to increased phosphorylation of acetyl coA carboxylase (ACC). The maximal effect was reached within 12h and sustained up to 48h. After 24h exposure to metformin (0.5-1mM), rat beta-cells exhibited a reduced secretory and synthetic responsiveness to 10mM glucose, which was also the case following 24h culture with the AMPK-activator 5-amino-imidazole-4-carboxamide riboside (AICAR; 1mM). Longer metformin exposure (>24h) resulted in a progressive increase in apoptotic beta-cells as was also reported for AICAR; metformin-induced apoptosis was reduced by compound C, an AMPK-inhibitor. As with AICAR, metformin activated c-Jun-N-terminal kinase (JNK) and caspase-3 prior to the appearance of apoptosis. It is concluded that metformin-induced AMPK-activation in beta-cells reduces their glucose responsiveness and may, following sustained exposure, result in apoptosis.
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Affiliation(s)
- Benjamin A Kefas
- Diabetes Research Center, Partner of the Juvenile Diabetes Research Center for Beta-cell Therapy in Europe, Brussels Free University-VUB, Laarbeeklaan 103, B-1090 Brussels, Belgium
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15
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Van de Casteele M, Kefas BA, Cai Y, Heimberg H, Scott DK, Henquin JC, Pipeleers D, Jonas JC. Prolonged culture in low glucose induces apoptosis of rat pancreatic beta-cells through induction of c-myc. Biochem Biophys Res Commun 2004; 312:937-44. [PMID: 14651961 DOI: 10.1016/j.bbrc.2003.11.013] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Prolonged culture in low-glucose concentrations (</=5mM) induces apoptosis in pancreatic beta-cells by a poorly defined mechanism. We now show that, in both purified rat beta-cells and isolated rat islets, culture in the presence of 3 or 5mM (G3-G5) instead of 10mM glucose (G10) induces a large increase in c-myc expression before onset of a caspase-dependent apoptosis. These effects were prevented by addition of leucine and glutamine to G3 and G5, and were mimicked by addition of the mitochondrial poison azide to G10. In contrast, inhibition of Ca(2+) influx and insulin secretion with diazoxide under control conditions did not stimulate islet c-myc expression nor beta-cell apoptosis. In rat beta-cells, adenovirus-mediated c-myc overexpression increased their rate of apoptosis, whereas antisense-c-myc expression reduced low-glucose-induced apoptosis by approximately 50%. In the insulin producing MIN6 cell line, apoptosis induction by either low glucose or an activator of AMP-activated protein kinase (AMPK) was associated with c-myc mRNA and protein upregulation. In conclusion, stimulation of beta-cell apoptosis by prolonged culture at low glucose partly results from early and sustained induction of beta-cell c-myc expression. These effects may be due to sustained restriction in nutrient-derived metabolic signals.
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16
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Park H, Ahn Y, Park CK, Chung HY, Park Y. Interleukin-6 protects MIN6 beta cells from cytokine-induced apoptosis. Ann N Y Acad Sci 2004; 1005:242-9. [PMID: 14679069 DOI: 10.1196/annals.1288.036] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Host nonspecific beta cell injury by cytokines has been implicated in the process of early islet graft dysfunction. Islet transplant destruction by cytokines released from inflammatory cells that infiltrate the graft is thought to be mainly mediated by NF-kappaB-dependent nitric oxide (NO) production by the islet. In this study, we aimed to evaluate the role of IL-6 in making a beta cell resistant to cytokine-induced apoptosis by decreasing the NF-kappaB-dependent NO production and compared the result with that of the expression of a dominant negative inhibitor of NF-kappaB (DN NF-kappaB). Incubation of MIN6 cells with IL-1beta, IFN-gamma, and TNF-alpha (cytomix) increased production of nitrites, with increased expression of iNOS mRNA. When treated with cytomix, the DN NF-kappaB-transfected mutant demonstrated significantly less nitrite production and apoptosis than parent MIN6. NO production was effectively blocked by IL-6 as well as by N-monomethyl-l-arginine (l-NMMA). Inhibition of the NO production led to decreased rate of apoptosis accompanied by downregulation of the proapoptotic molecule Bax and increased expression of the antiapoptotic molecule Bcl-2 and Bcl-x(L). These data indicate that cytokine-induced cell death in the MIN6 beta cell line involves mechanisms that are, in part, NF-kappaB- and NO-dependent. Inhibition of the NO production by the incubation of the MIN6 cells by the pretreatment of IL-6 or l-NMMA is cytoprotective and can be used as a substitute for the expression of DN NF-kappaB.
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Affiliation(s)
- Hyewon Park
- Division of Endocrinology and Metabolism, Department of Internal Medicine and Microbiology, Hanyang and Seoul National University, Seoul, Korea
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17
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Ling Z, Van de Casteele M, Dong J, Heimberg H, Haefliger JA, Waeber G, Schuit F, Pipeleers D. Variations in IB1/JIP1 expression regulate susceptibility of beta-cells to cytokine-induced apoptosis irrespective of C-Jun NH2-terminal kinase signaling. Diabetes 2003; 52:2497-502. [PMID: 14514632 DOI: 10.2337/diabetes.52.10.2497] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
We previously reported that interleukin-1beta (IL-1beta) alone does not cause apoptosis of beta-cells, whereas when combined with gamma-interferon (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha), it exerts a distinct apoptotic effect. Studies in beta-cell lines indicated that IL-1beta reduced expression of islet brain (IB)-1/JNK interacting protein (JIP)-1, a JNK scaffold protein with antiapoptotic action. We examined whether variations in IB1/JIP-1 expression in purified primary beta-cells affect their susceptibility to cytokine-induced apoptosis. Exposure to IL-1beta for 24 h decreased cellular IB1/JIP-1 content by 66 +/- 17%; this IL-1beta effect was maintained in the presence of TNF-alpha + IFN-gamma, which did not influence IB1/JIP-1 levels by themselves. Addition of IL-1beta to TNF-alpha + IFN-gamma increased apoptosis from 20 +/- 2% to 59 +/- 5%. A similar increase in TNF-alpha + IFN-gamma-induced apoptosis was produced by adenoviral expression of antisense IB1/JIP-1 and was not further enhanced by addition of IL-1beta, indicating that IL-1beta-mediated suppression of IB1/JIP-1 in beta-cells increases their susceptibility to cytokine-induced apoptosis. However, adenovirally mediated overexpression of IB1/JIP-1 also potentiated TNF-alpha + IFN-gamma-induced apoptosis, suggesting that the antiapoptotic effect of IB1/JIP-1 depends on well-defined cellular levels. We conclude that the IB1/JIP-1 level in beta-cells can control their susceptibility to apoptosis independent of JNK signaling.
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Affiliation(s)
- Zhidong Ling
- Diabetes Research Center, Brussels Free University-VUB, Brussels, Belgium.
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18
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Jambal P, Masterson S, Nesterova A, Bouchard R, Bergman B, Hutton JC, Boxer LM, Reusch JEB, Pugazhenthi S. Cytokine-mediated down-regulation of the transcription factor cAMP-response element-binding protein in pancreatic beta-cells. J Biol Chem 2003; 278:23055-65. [PMID: 12679364 DOI: 10.1074/jbc.m212450200] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Cytokines are known to induce apoptosis of pancreatic beta-cells. Impaired expression of the anti-apoptotic gene bcl-2 is one of the mechanisms involved. In this study, we identified a defect involving transcription factor cAMP-response element-binding protein (CREB) in the expression of bcl-2. Exposure of mouse pancreatic beta-cell line, MIN6 cells, to cytokines (interleukin-1beta, tumor necrosis factor-alpha, and interferon-gamma) led to a significant (p < 0.01) decrease in Bcl-2 protein and mRNA levels. Cytokines decreased (56%) the activity of the bcl-2 promoter that contains a cAMP-response element (CRE) site. Similar decreases were seen with a luciferase reporter gene driven by tandem repeats of CRE and a CREB-specific Gal4-luciferase reporter, suggesting a defect at the level of CREB. The active phospho form (serine 133) of CREB diminished significantly (p < 0.01) in cells exposed to cytokines. Examination of signaling pathways upstream of CREB revealed a reduction in the active form of Akt. Cytokine-induced decrease of bcl-2 promoter activity was partially restored when cells were cotransfected with a constitutively active form of Akt. Several end points of cytokine action including decreases in phospho-CREB, phospho-Akt, and BCl-2 levels and activation of caspase-9 were observed in isolated mouse islets. Overexpression of wild-type CREB in MIN6 cells by plasmid transfection and adenoviral infection led to protection against cytokine-induced apoptosis. Adenoviral transfer of dominant-negative forms of CREB, on the other hand, resulted in activation of caspase-9 and exaggeration of cytokine-induced beta-cell apoptosis. Together, these results point to CREB as a novel target for strategies aimed at improving the survival of beta-cells.
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Affiliation(s)
- Purevsuren Jambal
- Department of Medicine, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA
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Kefas BA, Heimberg H, Vaulont S, Meisse D, Hue L, Pipeleers D, Van de Casteele M. AICA-riboside induces apoptosis of pancreatic beta cells through stimulation of AMP-activated protein kinase. Diabetologia 2003; 46:250-4. [PMID: 12627324 DOI: 10.1007/s00125-002-1030-3] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2002] [Revised: 10/16/2002] [Indexed: 11/26/2022]
Abstract
AIMS/HYPOTHESIS Prolonged exposure of beta cells to low glucose concentrations triggers their apoptosis and is known to activate AMP-activated protein kinase (AMPK) in beta cell lines. We examined whether prolonged activation of AMPK can trigger apoptosis in rodent beta cells. METHODS Primary beta cells were FACS-purified from rats, and from wild-type and AMPK(alpha2)-deficient mice. AMPK activation in beta cells was induced by the adenosine analog AICA-riboside and detected by immunoblotting using a phosphospecific antibody. Apoptosis of rodent beta cells was monitored by FACS analysis of beta cell DNA content, by direct counting of apoptotic cells using fluorescence microscopy, or by measurement of their caspase-3 activity. RESULTS Dose-dependent and time-dependent apoptosis of the cells, concommittant with an activation of caspase-3, were suppressed by the caspase inhibitors zVAD-fmk and zDEVD-fmk. Apoptosis induction by AICA-riboside was also prevented by adding the MAPK-inhibitor SB203580 which blocked the AICA-riboside-induced phosphorylation of AMPK. Beta cells isolated from AMPK-(alpha2)-deficient mice were resistant against AICA-riboside induced apoptosis. CONCLUSION/INTERPRETATION Sustained activation of AMPK by AICA-riboside can trigger a caspase-dependent apoptosis of pancreatic beta cells.
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Affiliation(s)
- B A Kefas
- Diabetes Research Center, Free Brussels University-VUB, Laarbeeklaan 103, 1090 Brussels, Belgium
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20
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Meisse D, Van de Casteele M, Beauloye C, Hainault I, Kefas BA, Rider MH, Foufelle F, Hue L. Sustained activation of AMP-activated protein kinase induces c-Jun N-terminal kinase activation and apoptosis in liver cells. FEBS Lett 2002; 526:38-42. [PMID: 12208500 DOI: 10.1016/s0014-5793(02)03110-1] [Citation(s) in RCA: 168] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The aim of this work was to study the effect of a sustained activation of AMP-activated protein kinase (AMPK) on liver cell survival. AMPK activation was achieved by incubating FTO2B cells with AICA-riboside, which is transformed into ZMP, an AMP analogue, or by adenoviral transfection of hepatocytes with a constitutively active form of AMPK. Prolonged AMPK activation triggered apoptosis and activated c-Jun N-terminal kinase (JNK) and caspase-3. Experiments with iodotubercidin, dicoumarol and z-VAD-fmk, which inhibited AMPK, JNK and caspase activation, respectively, supported the notion that prolonged AMPK activation in liver cells induces apoptosis through an activation pathway that involves JNK and caspase-3.
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Affiliation(s)
- Delphine Meisse
- Hormone and Metabolic Research Unit, University of Louvain Medical School and Christian de Duve International Institute of Molecular and Cellular Pathology, Brussels, Belgium.
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