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Ergün S, Aslan S, Demir D, Kayaoğlu S, Saydam M, Keleş Y, Kolcuoğlu D, Taşkurt Hekim N, Güneş S. Beyond Death: Unmasking the Intricacies of Apoptosis Escape. Mol Diagn Ther 2024; 28:403-423. [PMID: 38890247 PMCID: PMC11211167 DOI: 10.1007/s40291-024-00718-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/14/2024] [Indexed: 06/20/2024]
Abstract
Apoptosis, or programmed cell death, maintains tissue homeostasis by eliminating damaged or unnecessary cells. However, cells can evade this process, contributing to conditions such as cancer. Escape mechanisms include anoikis, mitochondrial DNA depletion, cellular FLICE inhibitory protein (c-FLIP), endosomal sorting complexes required for transport (ESCRT), mitotic slippage, anastasis, and blebbishield formation. Anoikis, triggered by cell detachment from the extracellular matrix, is pivotal in cancer research due to its role in cellular survival and metastasis. Mitochondrial DNA depletion, associated with cellular dysfunction and diseases such as breast and prostate cancer, links to apoptosis resistance. The c-FLIP protein family, notably CFLAR, regulates cell death processes as a truncated caspase-8 form. The ESCRT complex aids apoptosis evasion by repairing intracellular damage through increased Ca2+ levels. Antimitotic agents induce mitotic arrest in cancer treatment but can lead to mitotic slippage and tetraploid cell formation. Anastasis allows cells to resist apoptosis induced by various triggers. Blebbishield formation suppresses apoptosis indirectly in cancer stem cells by transforming apoptotic cells into blebbishields. In conclusion, the future of apoptosis research offers exciting possibilities for innovative therapeutic approaches, enhanced diagnostic tools, and a deeper understanding of the complex biological processes that govern cell fate. Collaborative efforts across disciplines, including molecular biology, genetics, immunology, and bioinformatics, will be essential to realize these prospects and improve patient outcomes in diverse disease contexts.
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Affiliation(s)
- Sercan Ergün
- Department of Medical Biology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey.
- Department of Multidisciplinary Molecular Medicine, Institute of Graduate Studies, Ondokuz Mayis University, Samsun, Turkey.
| | - Senanur Aslan
- Department of Multidisciplinary Molecular Medicine, Institute of Graduate Studies, Ondokuz Mayis University, Samsun, Turkey
| | - Dilbeste Demir
- Department of Medical Biology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey
| | - Sümeyye Kayaoğlu
- Department of Medical Biology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey
| | - Mevsim Saydam
- Department of Medical Biology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey
| | - Yeda Keleş
- Department of Medical Biology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey
| | - Damla Kolcuoğlu
- Department of Medical Biology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey
| | - Neslihan Taşkurt Hekim
- Department of Medical Biology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey
- Department of Multidisciplinary Molecular Medicine, Institute of Graduate Studies, Ondokuz Mayis University, Samsun, Turkey
| | - Sezgin Güneş
- Department of Medical Biology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey
- Department of Multidisciplinary Molecular Medicine, Institute of Graduate Studies, Ondokuz Mayis University, Samsun, Turkey
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2
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Ferreira MPA, Ranjan S, Kinnunen S, Correia A, Talman V, Mäkilä E, Barrios-Lopez B, Kemell M, Balasubramanian V, Salonen J, Hirvonen J, Ruskoaho H, Airaksinen AJ, Santos HA. Drug-Loaded Multifunctional Nanoparticles Targeted to the Endocardial Layer of the Injured Heart Modulate Hypertrophic Signaling. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2017; 13:1701276. [PMID: 28714245 DOI: 10.1002/smll.201701276] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 05/31/2017] [Indexed: 05/23/2023]
Abstract
Ischemic heart disease is the leading cause of death globally. Severe myocardial ischemia results in a massive loss of myocytes and acute myocardial infarction, the endocardium being the most vulnerable region. At present, current therapeutic lines only ameliorate modestly the quality of life of these patients. Here, an engineered nanocarrier is reported for targeted drug delivery into the endocardial layer of the left ventricle for cardiac repair. Biodegradable porous silicon (PSi) nanoparticles are functionalized with atrial natriuretic peptide (ANP), which is known to be expressed predominantly in the endocardium of the failing heart. The ANP-PSi nanoparticles exhibit improved colloidal stability and enhanced cellular interactions with cardiomyocytes and non-myocytes with minimal toxicity. After confirmation of good retention of the radioisotope 111-Indium in relevant physiological buffers over 4 h, in vivo single-photon emission computed tomography (SPECT/CT) imaging and autoradiography demonstrate increased accumulation of ANP-PSi nanoparticles in the ischemic heart, particularly in the endocardial layer of the left ventricle. Moreover, ANP-PSi nanoparticles loaded with a novel cardioprotective small molecule attenuate hypertrophic signaling in the endocardium, demonstrating cardioprotective potential. These results provide unique insights into the development of nanotherapies targeted to the injured region of the myocardium.
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Affiliation(s)
- Mónica P A Ferreira
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, FI-00014, Finland
| | - Sanjeev Ranjan
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, FI-00014, Finland
- Department of Chemistry, University of Helsinki, Helsinki, FI-00014, Finland
| | - Sini Kinnunen
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, FI-00014, Finland
| | - Alexandra Correia
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, FI-00014, Finland
| | - Virpi Talman
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, FI-00014, Finland
| | - Ermei Mäkilä
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, FI-00014, Finland
- Laboratory of Industrial Physics, Department of Physics, University of Turku, Turku, FI-20014, Finland
| | | | - Marianna Kemell
- Department of Chemistry, University of Helsinki, Helsinki, FI-00014, Finland
| | - Vimalkumar Balasubramanian
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, FI-00014, Finland
| | - Jarno Salonen
- Laboratory of Industrial Physics, Department of Physics, University of Turku, Turku, FI-20014, Finland
| | - Jouni Hirvonen
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, FI-00014, Finland
| | - Heikki Ruskoaho
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, FI-00014, Finland
| | - Anu J Airaksinen
- Department of Chemistry, University of Helsinki, Helsinki, FI-00014, Finland
| | - Hélder A Santos
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, FI-00014, Finland
- Helsinki Institute of Life Science, HiLIFE, University of Helsinki, Helsinki, FI-00014, Finland
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3
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Sun X, Mao Y, Dai P, Li X, Gu W, Wang H, Wu G, Ma J, Huang S. Mitochondrial dysfunction is involved in the aggravation of periodontitis by diabetes. J Clin Periodontol 2017; 44:463-471. [PMID: 28207937 DOI: 10.1111/jcpe.12711] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2017] [Indexed: 12/17/2022]
Abstract
AIM To elucidate whether mitochondrial dysfunction contributes to aggravated periodontitis in diabetes. MATERIALS AND METHODS Sixty-four wistar rats were randomly assigned into four groups: control, periodontitis, diabetes, and diabetic periodontitis. Two weeks after induction of diabetes, periodontitis was induced by silk ligation for 2 weeks and thereafter evaluated by assessing alveolar bone loss and apoptosis of periodontium cells. Mitochondrial oxidative stress was detected by MitoSOX staining. Mitochondrial function was determined by measuring ATP production, and by assessing mitochondrial DNA copy number, activities of electron transport chain complexes, and biogenesis with real-time PCR. RESULTS Significantly severer bone loss, enhanced periodontium cell apoptosis, and mitochondrial oxidative stress were found in the rats with diabetic periodontitis than the others. Furthermore, diabetic rats with periodontitis presented severer mitochondrial dysfunction than lean rats with periodontitis, as reflected by compromised ATP production, decreased mitochondrial DNA copy number, reduced gene expression of electron transport chain complex I subunits, and impaired mitochondrial biogenesis (p < 0.05). Multiple regression analysis further indicated a close correlation between these mitochondrial events and bone loss in diabetic periodontitis. CONCLUSIONS Mitochondrial dysfunction was positive correlated to aggravated periodontitis in diabetes and might represent a therapeutic target for diabetic periodontitis.
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Affiliation(s)
- Xiaoyu Sun
- Department of Periodontology, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China.,Institute of Stomatology, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China.,Department of Oral Implantology and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Yixin Mao
- Institute of Stomatology, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China.,Department of Prosthodontics, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China
| | - Panpan Dai
- Institute of Stomatology, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China.,Department of Prosthodontics, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China
| | - Xumin Li
- Institute of Stomatology, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China.,Department of Prosthodontics, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China
| | - Weiyan Gu
- Institute of Stomatology, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China.,Department of Prosthodontics, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China
| | - Huining Wang
- Department of Periodontology, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China
| | - Gang Wu
- Department of Oral Implantology and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands
| | - Jianfeng Ma
- Institute of Stomatology, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China.,Department of Prosthodontics, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China
| | - Shengbin Huang
- Institute of Stomatology, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China.,Department of Oral Implantology and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Amsterdam, The Netherlands.,Department of Prosthodontics, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, China
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4
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Liu X, Tang L, Chen B, Jiang W. Role of sodium nitroprusside in regulating retinal ganglion cell damage through mitochondrial transcription factor A. Neurosci Lett 2016; 635:90-96. [PMID: 27789248 DOI: 10.1016/j.neulet.2016.10.045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 10/09/2016] [Accepted: 10/23/2016] [Indexed: 11/29/2022]
Abstract
Accumulating evidence has reported that nitric oxide (NO) can be cytotoxic and induce apoptosis. NO can also be genotoxic and cause DNA damage and mutations. It has been shown that NO damages mitochondrial DNA (mtDNA) to a greater extent than nuclear DNA. Sodium Nitroprusside (SNP), a NO donor, could efficiently promote NO formation. The viability of retinal ganglion cells (RGC) and the mtDNA copy numbers could also be altered by SNP conduction. Mitochondrial transcription factor A (TFAM), an mtDNA transcription factor, plays an essential role in the maintenance of mtDNA and mitochondrial homeostasis. The expression of TFAM was up-regulated by low dose SNP while down-regulated by high dose SNP. TFAM overexpression attenuated the regulatory effect of SNP on RGC viability and mtDNA numbers, while TFAM inhibition even amplified the regulatory effect of SNP. Moreover, the expression of apoptosis-related proteins in the mitochondria, Bcl-2 and Bax, were both altered by SNP treatment. These results suggested that TFAM impacted in SNP regulation of RGC viability and mtDNA numbers through the mitochondria-dependent pathway mediated by Bcl-2 and Bax subfamily.
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Affiliation(s)
- Xiao Liu
- Department of Ophthalmology, The Second Xiangya hospital of Central South University, No. 139, Ren Min Zhong Road, Changsha 410008, China
| | - Luosheng Tang
- Department of Ophthalmology, The Second Xiangya hospital of Central South University, No. 139, Ren Min Zhong Road, Changsha 410008, China
| | - Baihua Chen
- Department of Ophthalmology, The Second Xiangya hospital of Central South University, No. 139, Ren Min Zhong Road, Changsha 410008, China
| | - Wenmin Jiang
- Department of Ophthalmology, The Second Xiangya hospital of Central South University, No. 139, Ren Min Zhong Road, Changsha 410008, China.
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5
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Effect of diabetes on biodistribution, nephrotoxicity and antitumor activity of cisplatin in mice. Chem Biol Interact 2015; 229:119-31. [DOI: 10.1016/j.cbi.2015.01.027] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 12/20/2014] [Accepted: 01/07/2015] [Indexed: 12/18/2022]
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6
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High levels of Cellular Prion Protein improve astrocyte development. FEBS Lett 2012; 587:238-44. [DOI: 10.1016/j.febslet.2012.11.032] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 10/31/2012] [Accepted: 11/28/2012] [Indexed: 11/21/2022]
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7
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Michel S, Wanet A, De Pauw A, Rommelaere G, Arnould T, Renard P. Crosstalk between mitochondrial (dys)function and mitochondrial abundance. J Cell Physiol 2012; 227:2297-310. [PMID: 21928343 DOI: 10.1002/jcp.23021] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A controlled regulation of mitochondrial mass through either the production (biogenesis) or the degradation (mitochondrial quality control) of the organelle represents a crucial step for proper mitochondrial and cell function. Key steps of mitochondrial biogenesis and quality control are overviewed, with an emphasis on the role of mitochondrial chaperones and proteases that keep mitochondria fully functional, provided the mitochondrial activity impairment is not excessive. In this case, the whole organelle is degraded by mitochondrial autophagy or "mitophagy." Beside the maintenance of adequate mitochondrial abundance and functions for cell homeostasis, mitochondrial biogenesis might be enhanced, through discussed signaling pathways, in response to various physiological stimuli, like contractile activity, exposure to low temperatures, caloric restriction, and stem cells differentiation. In addition, mitochondrial dysfunction might also initiate a retrograde response, enabling cell adaptation through increased mitochondrial biogenesis.
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Affiliation(s)
- Sébastien Michel
- Laboratory of Biochemistry and Cell Biology (URBC), NARILIS (Namur Research Institute for Life Sciences), University of Namur (FUNDP), Namur, Belgium
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8
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Fekkar A, Balloy V, Pionneau C, Marinach-Patrice C, Chignard M, Mazier D. Secretome of human bronchial epithelial cells in response to the fungal pathogen Aspergillus fumigatus analyzed by differential in-gel electrophoresis. J Infect Dis 2012; 205:1163-72. [PMID: 22357658 DOI: 10.1093/infdis/jis031] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND For years, the analysis of innate responses to the major mold pathogen Aspergillus fumigatus has been restricted to specialized cells, such as professional phagocytes. More recently, the contribution of the airway epithelial barrier has been assessed and studies have shown that it was able to sense and react to the Aspergillus infection, for example, by producing cytokines. METHODS To further explore the reaction of the respiratory epithelium to the fungus, we analyzed the proteome response of a human bronchial epithelial cell line to Aspergillus infection using difference gel electrophoresis. We studied the protein pattern of BEAS-2B cell culture supernatant after interaction of the cells with Aspergillus during a 15-hour coculture. RESULTS We found formerly unknown aspects of bronchial cell behavior during Aspergillus infection: bronchial cells are able to develop both cellular defense mechanisms (ie, thioredoxin system activation) and immune reactions (ie, lysosomal degranulation and cathepsin activation) in response to the fungal aggression. CONCLUSIONS Bronchial epithelial cells appear to be a more important effector of antifungal defense than expected. Degranulation of lysosomal enzymes that might be responsible for both fungal growth inhibition and host cell damage suggests that inductors/inhibitors of these pathways may be potential targets of therapeutic intervention.
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Affiliation(s)
- A Fekkar
- Institut National de la Santé et de la Recherche Médicale (INSERM), U945, Université Pierre et Marie Curie-Paris 6, Paris, France.
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9
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Colletti GA, Miedel MT, Quinn J, Andharia N, Weisz OA, Kiselyov K. Loss of lysosomal ion channel transient receptor potential channel mucolipin-1 (TRPML1) leads to cathepsin B-dependent apoptosis. J Biol Chem 2012; 287:8082-91. [PMID: 22262857 DOI: 10.1074/jbc.m111.285536] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Mucolipidosis type IV (MLIV) is a lysosomal storage disease caused by mutations in the gene MCOLN1, which codes for the transient receptor potential family ion channel TRPML1. MLIV has an early onset and is characterized by developmental delays, motor and cognitive deficiencies, gastric abnormalities, retinal degeneration, and corneal cloudiness. The degenerative aspects of MLIV have been attributed to cell death, whose mechanisms remain to be delineated in MLIV and in most other storage diseases. Here we report that an acute siRNA-mediated loss of TRPML1 specifically causes a leak of lysosomal protease cathepsin B (CatB) into the cytoplasm. CatB leak is associated with apoptosis, which can be prevented by CatB inhibition. Inhibition of the proapoptotic protein Bax prevents TRPML1 KD-mediated apoptosis but does not prevent cytosolic release of CatB. This is the first evidence of a mechanistic link between acute TRPML1 loss and cell death.
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Affiliation(s)
- Grace A Colletti
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
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10
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Xiao Z, Yang M, Lv Q, Wang W, Deng M, Liu X, He Q, Chen X, Chen M, Fang L, Xie X, Hu J. P2Y11 impairs cell proliferation by induction of cell cycle arrest and sensitizes endothelial cells to cisplatin-induced cell death. J Cell Biochem 2011; 112:2257-65. [PMID: 21503959 DOI: 10.1002/jcb.23144] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Extracellular ATP mediates a wide range of physiological effects, including cell proliferation, differentiation, maturation, and migration. However, the effect of ATP on cell proliferation has been contradictory, and the mechanism is not fully understood. In the current study, we found that extracellular ATP significantly inhibited the proliferation of human umbilical vein endothelial cells (HUVECs) and human aortic endothelial cells (HAECs). Treatment with ATP did not induce cell apoptosis but instead induced cell cycle arrest in S phase. ATP induced the phosphorylation of ERK1/2, but the ERK inhibitors, U0126 and PD9809, did not regulate the inhibition of cell proliferation induced by ATP. However, ATP-induced inhibition of cell proliferation was blocked by suramin, a nonspecific antagonist of the P2Y receptors, and endothelial cells expressed P2Y11, a P2Y receptor that specifically binds ATP. Moreover, the down-regulation of P2Y11 by RNA interference not only reversed the inhibition of cell proliferation but also ameliorated cell cycle arrest in S phase. In addition, P2Y11 sensitized endothelial cells to cisplatin-induced cell death by down-regulation of the expression of Bcl-2. Taken together, these results suggest that extracellular ATP impairs cell proliferation by triggering signaling to induce cell cycle arrest and sensitizes cell to death via P2Y11 in endothelial cells.
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Affiliation(s)
- Zhilin Xiao
- Department of Geriatric Cardiology, Xiangya Hospital, Central South University, Changsha 410008, China
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Rommelaere G, Michel S, Malaisse J, Charlier S, Arnould T, Renard P. Hypersensitivity of A8344G MERRF mutated cybrid cells to staurosporine-induced cell death is mediated by calcium-dependent activation of calpains. Int J Biochem Cell Biol 2011; 44:139-49. [PMID: 22037425 DOI: 10.1016/j.biocel.2011.10.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Revised: 10/13/2011] [Accepted: 10/16/2011] [Indexed: 11/18/2022]
Abstract
Mutations in the mitochondrial DNA can lead to the development of mitochondrial diseases such as Myoclonic Epilepsy with Ragged Red Fibers (MERRF) or Mitochondrial Encephalomyopathy, Lactic Acidosis and Stroke-like episodes (MELAS). We first show that human 143B-derived cybrid cells harboring either the A8344G (MERRF) or the A3243G (MELAS) mutation, are more prone to undergo apoptosis then their wild-type counterpart, when challenged with various apoptotic inducers such as staurosporine, etoposide and TRAIL. In addition, investigating the mechanisms underlying A8344G cybrid cells hypersensitivity to staurosporine-induced cell death, we found that staurosporine treatment activates caspases independently of cytochrome c release in both wild-type and mutated cells. Caspases are activated, at least partly, through the activation of calcium-dependent calpain proteases, a pathway that is more strongly activated in mutated cybrid cells than in wild-type cells exposed to staurosporine. These results suggest that calcium homeostasis perturbation induced by mitochondrial dysfunction could predispose cells to apoptosis, a process that could take part into the progressive cell degeneration observed in MERRF syndrome, and more generally in mitochondrial diseases.
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Affiliation(s)
- Guillaume Rommelaere
- Laboratory of Biochemistry and Cell Biology (URBC), NARILIS (NAmur Research Institute for Life Sciences), University of Namur (FUNDP), Namur, Belgium
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