Mitochondrial dysfunction, caspase activation and caspase-dependent DNA fragmentation are involved in cell damage in many tissues. However, differentiated cardiomyocytes repress the expression of the canonical apoptotic pathway and their death during ischemia is caspase-independent. The atypical BH3-only protein Bnip3 is involved in the process leading to caspase-independent DNA fragmentation in cardiomyocytes. However, the pathway by which DNA degradation ensues following Bnip3 activation is not resolved. To identify the mechanism involved, we analyzed the interdependence of Bnip3, Nix and EndoG in mitochondrial damage and DNA fragmentation during experimental ischemia in neonatal rat ventricular cardiomyocytes. Our results show that the expression of EndoG and Bnip3 increases in the heart throughout development, while the caspase-dependent machinery is silenced. TUNEL-positive DNA damage, which depends on caspase activity in other cells, is caspase-independent in ischemic cardiomyocytes and ischemia-induced DNA high and low molecular weight fragmentation is blocked by repressing EndoG expression. Ischemia-induced EndoG translocation and DNA degradation are prevented by silencing the expression of Bnip3, but not Nix, or by overexpressing Bcl-xL. These data establish a link between Bnip3 and EndoG-dependent, TUNEL-positive, DNA fragmentation in ischemic cardiomyocytes in the absence of caspases, defining an alternative cell death pathway in postmitotic cells. ; The work was supported by the Ministry of Science and Innovation of Spain (SAF2005-02197 and SAF2008-02271) to DS and Programa de Suport a Grups de Recerca de Catalunya from the Government of Catalonia (AGAUR) (SGR2005-00628) and Ciberned from the Spanish Government to JXC, Instituto de Salud Carlos III -Ministerio de Sanidad y Consumo (FIS) (PI04/2537 and PS09/00140) to ML. JZ was recipient of a pre-doctoral fellowship (FPI program) from the Ministry of Education and Science of Spain and JY is recipient of a fellowship from the Universitat de Lleida. URLs: Ministry of Science and Innovation of Spain: http://www.micinn.es; AGAUR: http://www10.gencat.cat/agaur_web/AppJava/catala/index.jsp; Ministry of Education: http://www.educacion.es/portada.html; Instituto de Salud Carlos III: http://www.isciii.es/htdocs/index.jsp. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Glioblastoma multiforme is resistant to conventional anti-tumoral treatments due to its infiltrative nature and capability of relapse; therefore, research efforts focus on characterizing gliomagenesis and identifying molecular targets useful on therapy. New therapeutic strategies are being tested in patients, such as Histone deacetylase inhibitors (HDACi) either alone or in combination with other therapies. Here two HDACi included in clinical trials have been tested, suberanilohydroxamic acid (SAHA) and valproic acid (VPA), to characterize their effects on glioma cell growth in vitro and to determine the molecular changes that promote cancer cell death. We found that both HDACi reduce glioma cell viability, proliferation and clonogenicity. They have multiple effects, such as inducing the production of reactive oxygen species (ROS) and activating the mitochondrial apoptotic pathway, nevertheless cell death is not prevented by the pan-caspase inhibitor Q-VD-OPh. Importantly, we found that HDACi alter cell cycle progression by decreasing the expression of G2 checkpoint kinases Wee1 and checkpoint kinase 1 (Chk1). In addition, HDACi reduce the expression of proteins involved in DNA repair (Rad51), mitotic spindle formation (TPX2) and chromosome segregation (Survivin) in glioma cells and in human glioblastoma multiforme primary cultures. Therefore, HDACi treatment causes glioma cell entry into mitosis before DNA damage could be repaired and to the formation of an aberrant mitotic spindle that results in glioma cell death through mitotic catastrophe-induced apoptosis. ; This work was supported by the Spanish Ministry of Health grant ISCIII and the European Fund for Regional Development (FEDER) PS09/00140 to ML, ISCIII-PI080790 to JH and Programa de Suport a Grups de Recerca from the Government of Catalonia (AGAUR) (2009-SGR-346) to ML, DS and JXC.
Echocardiography has become an indispensable tool for the study of heart performance, improving the monitoring of individuals with cardiac diseases. Diverse genetic factors associated with echocardiographic measures have been previously reported. The impact of several apoptotic genes in heart development identified in experimental models prompted us to assess their potential association with human cardiac function. This study aimed at investigating the possible association of variants of apoptotic genes with echocardiographic traits and to identify new genetic markers associated with cardiac function. Genome wide data from different studies were obtained from public repositories. After quality control and imputation, a meta-analysis of individual association study results was performed. Our results confirmed the role of caspases and other apoptosis related genes with cardiac phenotypes. Moreover, enrichment analysis showed an over-representation of genes, including some apoptotic regulators, associated with Alzheimer's disease. We further explored this unexpected observation which was confirmed by genetic correlation analyses. Our findings show the association of apoptotic gene variants with echocardiographic indicators of heart function and reveal a novel potential genetic link between echocardiographic measures in healthy populations and cognitive decline later on in life. These findings may have important implications for preventative strategies combating Alzheimer's disease. ; General. Data collection and sharing for this project was partially funded by the Alzheimer's Disease Neuroimaging Initiative (ADNI) (National Institutes of Health Grant U01 AG024904) and DOD ADNI (Department of Defense award number W81XWH-12-2-0012). ADNI is funded by the National Institute on Aging, the National Institute of Biomedical Imaging and Bioengineering, and through generous contributions from the following: AbbVie, Alzheimer's Association; Alzheimer's Drug Discovery Foundation; Araclon Biotech; BioClinica, Inc.; Biogen; Bristol-Myers Squibb Company; CereSpir, Inc.; Cogstate; Eisai Inc.; Elan Pharmaceuticals, Inc.; Eli Lilly and Company; EuroImmun; F. Hoffmann-La Roche Ltd and its affiliated company Genentech, Inc.; Fujirebio; GE Healthcare; IXICO Ltd.; Janssen Alzheimer Immunotherapy Research & Development, LLC.; Johnson & Johnson Pharmaceutical Research & Development LLC.; Lumosity; Lundbeck; Merck & Co., Inc.; Meso Scale Diagnostics, LLC.; NeuroRx Research; Neurotrack Technologies; Novartis Pharmaceuticals Corporation; Pfizer Inc.; Piramal Imaging; Servier; Takeda Pharmaceutical Company; and Transition Therapeutics. The Canadian Institutes of Health Research is providing funds to support ADNI clinical sites in Canada. Private sector contributions are facilitated by the Foundation for the National Institutes of Health (www.fnih.org). The grantee organization is the Northern California Institute for Research and Education, and the study is coordinated by the Alzheimer's Therapeutic Research Institute at the University of Southern California. ADNI data are disseminated by the Laboratory for Neuro Imaging at the University of Southern California. For the Alzheimer's Disease Neuroimaging Initiative: Data used in preparation of this article were obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database (adni.loni.usc.edu). As such, the investigators within the ADNI contributed to the design and implementation of ADNI and/or provided data but did not participate in analysis or writing of this report. A complete listing of ADNI investigators can be found at: http://adni.loni.usc.edu/wp19content/uploads/how_to_apply/ADNI_Acknowledgement_List.pdf. The AddNeuroMed data are from a public-private partnership supported by EFPIA companies and SMEs as part of InnoMed (Innovative Medicines in Europe), an Integrated Project funded by the European Union of the Sixth Framework program priority FP6-2004-LIFESCIHEALTH-5. Clinical leads responsible for data collection are Iwona Kłoszewska (Lodz), Simon Lovestone (London), Patrizia Mecocci (Perugia), Hilkka Soininen (Kuopio), Magda Tsolaki (Thessaloniki), and Bruno Vellas (Toulouse), imaging leads are Andy Simmons (London), Lars-Olad Wahlund (Stockholm) and Christian Spenger (Zurich) and bioinformatics leads are Richard Dobson (London) and Stephen Newhouse (London). This dataset was downloaded from Synapse (https://doi.org/10.7303/syn2790911). Funding support for the Alzheimer's Disease Genetics Consortium (ADGC) was provided through the NIA Division of Neuroscience (U01-AG032984). This study was downloaded from NIH dbGaP repository (phs000372.v1). The Coronary Artery Risk Development in Young Adults Study (CARDIA) is conducted and supported by the National Heart, Lung, and Blood Institute (NHLBI) in collaboration with the University of Alabama at Birmingham (N01-HC95095 & N01-HC48047), University of Minnesota (N01-HC48048), Northwestern University (N01-HC48049), and Kaiser Foundation Research Institute (N01-HC48050). This manuscript was not approved by CARDIA. The opinions and conclusions contained in this publication are solely those of the authors, and are not endorsed by CARDIA or the NHLBI and should not be assumed to reflect the opinions or conclusions of either. Genotyping for the CARDIA GENEVA cohort was supported by grant U01 HG004729 from the National Human Genome Research Institute. This study was downloaded from NIH dbGaP repository (phs000285.v3.p2). The Cardiovascular Heart Study (CHS) was supported by contracts HHSN268201200036C, HHSN268200800007C, N01-HC85079, N01-HC-85080, N01-HC-85081, N01-HC-85082, N01-HC-85083, N01-HC-85084, N01-HC-85085, N01-HC-85086, N01-HC-35129, N01 HC-15103, N01 HC-55222, N01-HC-75150, N01-HC-45133, and N01-HC-85239; grant numbers U01 HL080295 and U01 HL130014 from the National Heart, Lung, and Blood Institute, and R01 AG-023629 from the National Institute on Aging, with additional contribution from the National Institute of Neurological Disorders and Stroke. A full list of principal CHS investigators and institutions can be found at https://chs-nhlbi.org/pi. This manuscript was not prepared in collaboration with CHS investigators and does not necessarily reflect the opinions or views of CHS or the NHLBI. Support for the genotyping through the CARe Study was provided by NHLBI Contract N01-HC-65226. This study was downloaded from NIH dbGaP repository (phs000287.v5.p1). The Framingham Heart Study is conducted and supported by the National Heart, Lung, and Blood Institute (NHLBI) in collaboration with Boston University (Contract No. N01-HC-25195 and HHSN268201500001I). This manuscript was not prepared in collaboration with investigators of the Framingham Heart Study and does not necessarily reflect the opinions or views of the Framingham Heart Study, Boston University, or NHLBI. "Funding for SHARe Affymetrix genotyping was provided by NHLBI Contract N02-HL64278. SHARe Illumina genotyping was provided under an agreement between Illumina and Boston University. Funding for Affymetrix genotyping of the FHS Omni cohorts was provided by Intramural NHLBI funds from Andrew D. Johnson and Christopher J. O'Donnell. This dataset was obtained from the NIH dbGaP repository (phs000007.v29.p10). The genotypic and associated phenotypic data used in the study, "Multi-Site Collaborative Study for Genotype-Phenotype Associations in Alzheimer's Disease (GenADA)" were provided by the GlaxoSmithKline, R&D Limited. The datasets used for analyses described in this manuscript were obtained from NIH dbGaP repository (phs000219.v1.p1). The Mayo Clinic Alzheimer's Disease Genetic Studies, led by Dr. Nilüfer Ertekin-Taner and Dr. Steven G. Younkin, Mayo Clinic, Jacksonville, FL using samples from the Mayo Clinic Study of Aging, the Mayo Clinic Alzheimer's Disease Research Center, and the Mayo Clinic Brain Bank. Data collection was supported through funding by NIA grants P50 AG016574, R01 AG032990, U01 AG046139, R01 AG018023, U01 AG006576, U01 AG006786, R01 AG025711, R01 AG017216, R01 AG003949, NINDS grant R01 NS080820, CurePSP Foundation, and support from Mayo Foundation. This dataset was downloaded from Synapse (https://doi.org/10.7303/syn5550404). The MESA study was supported by contracts HHSN268201500003I, N01-HC-95159, N01-HC-95160, N01-HC-95161, N01-HC-95162, N01-HC-95163, N01-HC-95164, N01-HC-95165, N01-HC-95166, N01-HC-95167, N01-HC-95168 and N01-HC-95169 from the National Heart, Lung, and Blood Institute, and by grants UL1-TR-000040, UL1-TR-001079, and UL1-TR-001420 from NCATS. The authors thank the other investigators, the staff, and the participants of the MESA study for their valuable contributions. A full list of participating MESA investigators and institutions can be found at http://www.mesa-nhlbi.org. This dataset was obtained from the NIH dbGaP repository (phs000209.v6.p2). The Neocodex-Murcia study was funded by the Fundación Alzheimur (Murcia), the Ministerio de Educación y Ciencia (Gobierno de España), Corporación Tecnológica de Andalucía and Agencia IDEA (Consejería de Innovación, Junta de Andalucía). The Diabetes Research Laboratory, Biomedical Research Foundation. University Hospital Clínico San Carlos has been supported by CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM); CIBERDEM is an ISCIII Project. The ROS/MAP study data were provided by the Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago. Data collection was supported through funding by NIA grants P30AG10161, R01AG15819, R01AG17917, R01AG30146, R01AG36836, U01AG32984, U01AG46152, the Illinois Department of Public Health, and the Translational Genomics Research Institute. This dataset was downloaded from Synapse (https://doi.org/10.7303/syn3219045). The TGEN study was supported by Kronos Life Sciences Laboratories, the National Institute on Aging (Arizona Alzheimer's Disease Center P30 AG19610, RO1 AG023193, Mayo Clinic Alzheimer's Disease Center P50 AG16574, and Intramural Research Program), the National Alzheimer's Coordinating Center (U01 AG016976), and the state of Arizona. TGEN investigators provided free access to genotype data to other researchers via Coriell Biorepositories (http://www.coriell.org). The results published here are in part based on data obtained from the AMP-AD Knowledge Portal accessed at https://doi.org/10.7303/syn2580853. D.S. research is supported by Grant 20153810 from Fundació La Marató de TV3 and Grant SAF2013-44942-R from the Ministerio de Economía y Competitividad (MINECO) and, with J.X.C., Grant 2009SGR-346 from the Agència de Gestió d'Ajuts Universitaris i de Recerca (AGAUR) from the Government of Catalonia. A.B. has a predoctoral contract from Fundació La Marató de TV3. A.R. research is also supported by grants PI13/02434 and PI16/01861. Acción Estratégica en Salud, integrated in the Spanish National R&D&I Plan and financed by ISCIII (Instituto de Salud Carlos III)-Subdirección General de Evaluación and the European Regional Development Fund (ERDF – "A way to make Europe"), by Fundación banca "La Caixa" and Grifols SA (GR@ACE project). This work was also partly supported by the ADAPTED consortium, which has received funding from the Innovative Medicines Initiative 2 Joint Undertaking under grant agreement No 115975. This Joint Undertaking receives support from the European Union's Horizon 2020 research and innovation program and the European Federation of Pharmaceutical Industries and Associations.
The neuronal long isoform of Fas Apoptotic Inhibitory Molecule (FAIM-L) protects from death receptor (DR)-induced apoptosis, yet its mechanism of protection remains unknown. Here, we show that FAIM-L protects rat neuronal Type II cells from Fas-induced apoptosis. XIAP has previously emerged as a molecular discriminator that is upregulated in Type II and downregulated in Type I apoptotic signaling. We demonstrate that FAIM-L requires sustained endogenous levels of XIAP to protect Type II cells as well as murine cortical neurons from Fas-induced apoptosis. FAIM-L interacts with the BIR2 domain of XIAP through an IAP-binding motif, the mutation of which impairs the antiapoptotic function of FAIM-L. Finally, we report that FAIM-L inhibits XIAP auto-ubiquitinylation and maintains its stability, thus conferring protection from apoptosis. Our results bring new understanding of the regulation of endogenous XIAP by a DR antagonist, pointing out at FAIM-L as a promising therapeutic tool for protection from apoptosis in pathological situations where XIAP levels are decreased. ; This work was funded by the Spanish Government Ministerio de Sanidad y Consumo (Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, CB06/05/1104 to J.X.C.), Ministerio de Economía y Competitividad (SAF2010–19953 to J.X.C.; SAF2012–31485 to V.J.Y.), Instituto de Salud Carlos III (CP11/00052 to M.F.S.), and the Generalitat de Catalunya (Suport als Grups de Recerca Consolidats 2009SGR346). F.M.-F. and L.P.-F. are supported by postgraduate fellowships from the Spanish Government Ministerio de Educación y Ciencia. J.U. is supported by a postgraduate fellowship from the Generalitat de Catalunya. R.S.M. and V.J.Y. were under the Juan de la Cierva and the Ramon y Cajal programs, respectively, from the Ministerio de Educación y Ciencia (Spain), cofinanced by the European Social Fund. M.F.S. is under the Miguel Servet program from the Instituto de Salud Carlos III and cofinanced by the European Regional Development Fund.
Death receptors (DRs) and their ligands are expressed in developing nervous system. However, neurons are generally resistant to death induction through DRs and rather their activation promotes neuronal outgrowth and branching. These results suppose the existence of DRs antagonists expressed in the nervous system. Fas apoptosis inhibitory molecule (FAIMS ) was first identified as a Fas antagonist in B-cells. Soon after, a longer alternative spliced isoform with unknown function was identified and named FAIML. FAIMS is widely expressed, including the nervous system, and we have shown previously that it promotes neuronal differentiation but it is not an anti-apoptotic molecule in this system. Here, we demonstrate that FAIML is expressed specifically in neurons, and its expression is regulated during the development. Expression could be induced by NGF through the extracellular regulated kinase pathway in PC12(pheochromocytoma cell line) cells. Contrary to FAIMS , FAIML does not increase the neurite outgrowth induced by neurotrophins and does not interfere with nuclear factor ĸB pathway activation as FAIMS does. Cells overexpressing FAIML are resistant to apoptotic cell death induced by DRs such as Fas or tumor necrosis factor R1. Reduction of endogenous expression by small interfering RNA shows that endogenousFAIML protects primary neurons from DR-induced cell death. The detailed analysis of this antagonism shows thatFAIML can bind to Fas receptor and prevent the activation of the initiator caspase-8 induced by Fas. In conclusion, our results indicate that FAIML could be responsible for maintaining initiator caspases inactive after receptor engagement protecting neurons from the cytotoxic action of death ligands. ; This work was supported by Spanish Government "Ministerio de Sanidad y Consumo" (contract number PI020051, PI04/2364, Redes Temáticas de Investigación Cooperativa, and CiberNed), Fundació La Caixa (Ayudas a la Investigación en Enfermedades Neurodegenerativas 02/055-00), Ministerio de Educacio´n y Ciencia (SAF-2005- 0176), and Generalitat de Catalunya (Suport als Grups de Recerca Consolidats and Distinció a Joves Investigadors). M.F.S., C.S., and M.J.P.-G. were supported by a postgraduate fellowship from the Spanish Government, Ministerio de Educación y Ciencia and Fondo de Investigación Sanitaria, respectively. R.G. holds a postgraduate fellowship from the Department d'Universitat, Recerca i Societat de la Informació (Generalitat de Catalunya) and Fons Social Europeu. N.B. is the recipient of a postgraduate fellowship from the Gobierno Vasco. V.J.Y. was under a Beatriu de Pino´s contract from Generalitat de Catalunya.
