1
|
Zocher S. Targeting neuronal epigenomes for brain rejuvenation. EMBO J 2024; 43:3312-3326. [PMID: 39009672 PMCID: PMC11329789 DOI: 10.1038/s44318-024-00148-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 05/21/2024] [Accepted: 05/28/2024] [Indexed: 07/17/2024] Open
Abstract
Aging is associated with a progressive decline of brain function, and the underlying causes and possible interventions to prevent this cognitive decline have been the focus of intense investigation. The maintenance of neuronal function over the lifespan requires proper epigenetic regulation, and accumulating evidence suggests that the deterioration of the neuronal epigenetic landscape contributes to brain dysfunction during aging. Epigenetic aging of neurons may, however, be malleable. Recent reports have shown age-related epigenetic changes in neurons to be reversible and targetable by rejuvenation strategies that can restore brain function during aging. This review discusses the current evidence that identifies neuronal epigenetic aging as a driver of cognitive decline and a promising target of brain rejuvenation strategies, and it highlights potential approaches for the specific manipulation of the aging neuronal epigenome to restore a youthful epigenetic state in the brain.
Collapse
Affiliation(s)
- Sara Zocher
- German Center for Neurodegenerative Diseases, Tatzberg 41, 01307, Dresden, Germany.
| |
Collapse
|
2
|
Dines M, Kes M, Ailán D, Cetkovich-Bakmas M, Born C, Grunze H. Bipolar disorders and schizophrenia: discrete disorders? Front Psychiatry 2024; 15:1352250. [PMID: 38745778 PMCID: PMC11091416 DOI: 10.3389/fpsyt.2024.1352250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 04/16/2024] [Indexed: 05/16/2024] Open
Abstract
Background With similarities in heritability, neurobiology and symptomatology, the question has been raised whether schizophrenia and bipolar disorder are truly distinctive disorders or belong to a continuum. This narrative review summarizes common and distinctive findings from genetics, neuroimaging, cognition and clinical course that may help to solve this ethiopathogenetic puzzle. Methods The authors conducted a literature search for papers listed in PubMed and Google Scholar, using the search terms "schizophrenia" and "bipolar disorder" combined with different terms such as "genes", "neuroimaging studies", "phenomenology differences", "cognition", "epidemiology". Articles were considered for inclusion if they were written in English or Spanish, published as full articles, if they compared subjects with schizophrenia and bipolar disorder, or subjects with either disorder with healthy controls, addressing differences between groups. Results Several findings support the hypothesis that schizophrenia and bipolar disorder are discrete disorders, yet some overlapping of findings exists. The evidence for heritability of both SZ and BD is obvious, as well as the environmental impact on individual manifestations of both disorders. Neuroimaging studies support subtle differences between disorders, it appears to be rather a pattern of irregularities than an unequivocally unique finding distinguishing schizophrenia from bipolar disorder. The cognitive profile displays differences between disorders in certain domains, such as premorbid intellectual functioning and executive functions. Finally, the timing and trajectory of cognitive impairment in both disorders also differs. Conclusion The question whether SZ and BD belong to a continuum or are separate disorders remains a challenge for further research. Currently, our research tools may be not precise enough to carve out distinctive, unique and undisputable differences between SZ and BD, but current evidence favors separate disorders. Given that differences are subtle, a way to overcome diagnostic uncertainties in the future could be the application of artificial intelligence based on BigData. Limitations Despite the detailed search, this article is not a full and complete review of all available studies on the topic. The search and selection of papers was also limited to articles in English and Spanish. Selection of papers and conclusions may be biased by the personal view and clinical experience of the authors.
Collapse
Affiliation(s)
- Micaela Dines
- Department of Psychiatry, Instituto de Neurología Cognitiva (INECO), Buenos Aires, Argentina
- Department of Psychiatry, Instituto de Neurociencia Cognitiva y Traslacional (Consejo Nacional de Investigaciones Científicas y Técnicas - Fundación INECO - Universidad Favaloro), Buenos Aires, Argentina
| | - Mariana Kes
- Department of Psychiatry, Instituto de Neurología Cognitiva (INECO), Buenos Aires, Argentina
- Department of Psychiatry, Instituto de Neurociencia Cognitiva y Traslacional (Consejo Nacional de Investigaciones Científicas y Técnicas - Fundación INECO - Universidad Favaloro), Buenos Aires, Argentina
| | - Delfina Ailán
- Department of Psychiatry, Instituto de Neurología Cognitiva (INECO), Buenos Aires, Argentina
- Department of Psychiatry, Instituto de Neurociencia Cognitiva y Traslacional (Consejo Nacional de Investigaciones Científicas y Técnicas - Fundación INECO - Universidad Favaloro), Buenos Aires, Argentina
| | - Marcelo Cetkovich-Bakmas
- Department of Psychiatry, Instituto de Neurología Cognitiva (INECO), Buenos Aires, Argentina
- Department of Psychiatry, Instituto de Neurociencia Cognitiva y Traslacional (Consejo Nacional de Investigaciones Científicas y Técnicas - Fundación INECO - Universidad Favaloro), Buenos Aires, Argentina
| | - Christoph Born
- Department of Psychiatry, Psychiatrie Schwäbisch Hall, Ringstraße, Germany
- Department of Psychiatry, Paracelsus Medical University, Nuremberg, Germany
| | - Heinz Grunze
- Department of Psychiatry, Psychiatrie Schwäbisch Hall, Ringstraße, Germany
- Department of Psychiatry, Paracelsus Medical University, Nuremberg, Germany
| |
Collapse
|
3
|
Agriesti F, Landini F, Tamma M, Pacelli C, Mazzoccoli C, Calice G, Ruggieri V, Capitanio G, Mori G, Piccoli C, Capitanio N. Bioenergetic profile and redox tone modulate in vitro osteogenesis of human dental pulp stem cells: new perspectives for bone regeneration and repair. Stem Cell Res Ther 2023; 14:215. [PMID: 37608350 PMCID: PMC10463344 DOI: 10.1186/s13287-023-03447-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 08/10/2023] [Indexed: 08/24/2023] Open
Abstract
BACKGROUND Redox signaling and energy metabolism are known to be involved in controlling the balance between self-renewal and proliferation/differentiation of stem cells. In this study we investigated metabolic and redox changes occurring during in vitro human dental pulp stem cells (hDPSCs) osteoblastic (OB) differentiation and tested on them the impact of the reactive oxygen species (ROS) signaling. METHODS hDPSCs were isolated from dental pulp and subjected to alkaline phosphatase and alizarin red staining, q-RT-PCR, and western blotting analysis of differentiation markers to assess achievement of osteogenic/odontogenic differentiation. Moreover, a combination of metabolic flux analysis and confocal cyto-imaging was used to profile the metabolic phenotype and to evaluate the redox tone of hDPSCs. RESULTS In differentiating hDPSCs we observed the down-regulation of the mitochondrial respiratory chain complexes expression since the early phase of the process, confirmed by metabolic flux analysis, and a reduction of the basal intracellular peroxide level in its later phase. In addition, dampened glycolysis was observed, thereby indicating a lower energy-generating phenotype in differentiating hDPSCs. Treatment with the ROS scavenger Trolox, applied in the early-middle phases of the process, markedly delayed OB differentiation of hDPSCs assessed as ALP activity, Runx2 expression, mineralization capacity, expression of stemness and osteoblast marker genes (Nanog, Lin28, Dspp, Ocn) and activation of ERK1/2. In addition, the antioxidant partly prevented the inhibitory effect on cell metabolism observed following osteogenic induction. CONCLUSIONS Altogether these results provided evidence that redox signaling, likely mediated by peroxide species, influenced the stepwise osteogenic expansion/differentiation of hDPSCs and contributed to shape its accompanying metabolic phenotype changes thus improving their efficiency in bone regeneration and repair.
Collapse
Affiliation(s)
- Francesca Agriesti
- Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy
- Laboratory of Pre-Clinical and Translational Research, IRCCS-CROB, Referral Cancer Center of Basilicata, 85028 Rionero in Vulture, Italy
| | - Francesca Landini
- Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy
| | - Mirko Tamma
- Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy
| | - Consiglia Pacelli
- Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy
| | - Carmela Mazzoccoli
- Laboratory of Pre-Clinical and Translational Research, IRCCS-CROB, Referral Cancer Center of Basilicata, 85028 Rionero in Vulture, Italy
| | - Giovanni Calice
- Laboratory of Pre-Clinical and Translational Research, IRCCS-CROB, Referral Cancer Center of Basilicata, 85028 Rionero in Vulture, Italy
| | - Vitalba Ruggieri
- Laboratory of Pre-Clinical and Translational Research, IRCCS-CROB, Referral Cancer Center of Basilicata, 85028 Rionero in Vulture, Italy
- Clinical Pathology Unit, “Madonna delle Grazie’’ Hospital, Matera, Italy
| | - Giuseppe Capitanio
- Department of Translational Biomedicine and Neuroscience “DiBraiN”, University of Bari “Aldo Moro”, 70124 Bari, Italy
| | - Giorgio Mori
- Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy
| | - Claudia Piccoli
- Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy
| | - Nazzareno Capitanio
- Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy
| |
Collapse
|
4
|
Amato I, Meurant S, Renard P. The Key Role of Mitochondria in Somatic Stem Cell Differentiation: From Mitochondrial Asymmetric Apportioning to Cell Fate. Int J Mol Sci 2023; 24:12181. [PMID: 37569553 PMCID: PMC10418455 DOI: 10.3390/ijms241512181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/27/2023] [Accepted: 07/28/2023] [Indexed: 08/13/2023] Open
Abstract
The study of the mechanisms underlying stem cell differentiation is under intensive research and includes the contribution of a metabolic switch from glycolytic to oxidative metabolism. While mitochondrial biogenesis has been previously demonstrated in number of differentiation models, it is only recently that the role of mitochondrial dynamics has started to be explored. The discovery of asymmetric distribution of mitochondria in stem cell progeny has strengthened the interest in the field. This review attempts to summarize the regulation of mitochondrial asymmetric apportioning by the mitochondrial fusion, fission, and mitophagy processes as well as emphasize how asymmetric mitochondrial apportioning in stem cells affects their metabolism, and thus epigenetics, and determines cell fate.
Collapse
Affiliation(s)
- Ilario Amato
- Ressearch Unit in Cell Biology (URBC), Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium; (I.A.); (S.M.)
| | - Sébastien Meurant
- Ressearch Unit in Cell Biology (URBC), Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium; (I.A.); (S.M.)
| | - Patricia Renard
- Ressearch Unit in Cell Biology (URBC), Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium; (I.A.); (S.M.)
- Mass Spectrometry Platform (MaSUN), Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
| |
Collapse
|
5
|
Segura AG, de la Serna E, Sugranyes G, Baeza I, Valli I, Díaz-Caneja C, Martín N, Moreno DM, Gassó P, Rodriguez N, Mas S, Castro-Fornieles J. Epigenetic age deacceleration in youth at familial risk for schizophrenia and bipolar disorder. Transl Psychiatry 2023; 13:155. [PMID: 37156786 PMCID: PMC10167217 DOI: 10.1038/s41398-023-02463-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 04/21/2023] [Accepted: 04/27/2023] [Indexed: 05/10/2023] Open
Abstract
Epigenetic modifications occur sequentially during the lifespan, but their pace can be altered by external stimuli. The onset of schizophrenia and bipolar disorder is critically modulated by stressors that may alter the epigenetic pattern, a putative signature marker of exposure to environmental risk factors. In this study, we estimated the age-related epigenetic modifications to assess the differences between young individuals at familial high risk (FHR) and controls and their association with environmental stressors. The sample included 117 individuals (6-17 years) at FHR (45%) and a control group (55%). Blood and saliva samples were used estimate the epigenetic age with six epigenetic clocks through methylation data. Environmental risk was measured with obstetric complications, socioeconomic statuses and recent stressful life events data. Epigenetic age was correlated with chronological age. FHR individuals showed epigenetic age deacceleration of Horvath and Hannum epigenetic clocks compared to controls. No effect of the environmental risk factors on the epigenetic age acceleration could be detected. Epigenetic age acceleration adjusted by cell counts showed that the FHR group was deaccelerated also with the PedBE epigenetic clock. Epigenetic age asynchronicities were found in the young at high risk, suggesting that offspring of affected parents follow a slower pace of biological aging than the control group. It still remains unclear which environmental stressors orchestrate the changes in the methylation pattern. Further studies are needed to better characterize the molecular impact of environmental stressors before illness onset, which could be critical in the development of tools for personalized psychiatry.
Collapse
Affiliation(s)
- Alex G Segura
- Department of Clinical Foundations, Pharmacology Unit, University of Barcelona, Barcelona, Spain
| | - Elena de la Serna
- Child and Adolescent Psychiatry and Psychology Department, 2021SGR01319, Institute of Neuroscience, Hospital Clínic de Barcelona, Barcelona, Spain
- Department of Medicine, Institute of Neuroscience, University of Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Gisela Sugranyes
- Child and Adolescent Psychiatry and Psychology Department, 2021SGR01319, Institute of Neuroscience, Hospital Clínic de Barcelona, Barcelona, Spain
- Department of Medicine, Institute of Neuroscience, University of Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Inmaculada Baeza
- Child and Adolescent Psychiatry and Psychology Department, 2021SGR01319, Institute of Neuroscience, Hospital Clínic de Barcelona, Barcelona, Spain
- Department of Medicine, Institute of Neuroscience, University of Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Isabel Valli
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Covadonga Díaz-Caneja
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
- Department of Child and Adolescent Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Nuria Martín
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
- Department of Child and Adolescent Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Dolores M Moreno
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
- Adolescent Inpatient Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain
- Psychiatry Department, Universidad Complutense de Madrid, Madrid, Spain
| | - Patricia Gassó
- Department of Clinical Foundations, Pharmacology Unit, University of Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Natalia Rodriguez
- Department of Clinical Foundations, Pharmacology Unit, University of Barcelona, Barcelona, Spain
| | - Sergi Mas
- Department of Clinical Foundations, Pharmacology Unit, University of Barcelona, Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
| | - Josefina Castro-Fornieles
- Child and Adolescent Psychiatry and Psychology Department, 2021SGR01319, Institute of Neuroscience, Hospital Clínic de Barcelona, Barcelona, Spain
- Department of Medicine, Institute of Neuroscience, University of Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| |
Collapse
|
6
|
Zocher S, Toda T. Epigenetic aging in adult neurogenesis. Hippocampus 2023; 33:347-359. [PMID: 36624660 DOI: 10.1002/hipo.23494] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 10/11/2022] [Accepted: 12/06/2022] [Indexed: 01/11/2023]
Abstract
Neural stem cells (NSCs) in the hippocampus generate new neurons throughout life, which functionally contribute to cognitive flexibility and mood regulation. Yet adult hippocampal neurogenesis substantially declines with age and age-related impairments in NSC activity underlie this reduction. Particularly, increased NSC quiescence and consequently reduced NSC proliferation are considered to be major drivers of the low neurogenesis levels in the aged brain. Epigenetic regulators control the gene expression programs underlying NSC quiescence, proliferation and differentiation and are hence critical to the regulation of adult neurogenesis. Epigenetic alterations have also emerged as central hallmarks of aging, and recent studies suggest the deterioration of the NSC-specific epigenetic landscape as a driver of the age-dependent decline in adult neurogenesis. In this review, we summarize the recently accumulating evidence for a role of epigenetic dysregulation in NSC aging and propose perspectives for future research directions.
Collapse
Affiliation(s)
- Sara Zocher
- Nuclear Architecture in Neural Plasticity and Aging Laboratory, German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany
| | - Tomohisa Toda
- Nuclear Architecture in Neural Plasticity and Aging Laboratory, German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany
- Institute of Medical Physics and Microtissue Engineering, Faculty of Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| |
Collapse
|
7
|
Al-Azab M, Safi M, Idiiatullina E, Al-Shaebi F, Zaky MY. Aging of mesenchymal stem cell: machinery, markers, and strategies of fighting. Cell Mol Biol Lett 2022; 27:69. [PMID: 35986247 PMCID: PMC9388978 DOI: 10.1186/s11658-022-00366-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 07/18/2022] [Indexed: 02/08/2023] Open
Abstract
Human mesenchymal stem cells (MSCs) are primary multipotent cells capable of differentiating into osteocytes, chondrocytes, and adipocytes when stimulated under appropriate conditions. The role of MSCs in tissue homeostasis, aging-related diseases, and cellular therapy is clinically suggested. As aging is a universal problem that has large socioeconomic effects, an improved understanding of the concepts of aging can direct public policies that reduce its adverse impacts on the healthcare system and humanity. Several studies of aging have been carried out over several years to understand the phenomenon and different factors affecting human aging. A reduced ability of adult stem cell populations to reproduce and regenerate is one of the main contributors to the human aging process. In this context, MSCs senescence is a major challenge in front of cellular therapy advancement. Many factors, ranging from genetic and metabolic pathways to extrinsic factors through various cellular signaling pathways, are involved in regulating the mechanism of MSC senescence. To better understand and reverse cellular senescence, this review highlights the underlying mechanisms and signs of MSC cellular senescence, and discusses the strategies to combat aging and cellular senescence.
Collapse
|
8
|
Franks AM. Reducing subspace models for large-scale covariance regression. Biometrics 2022; 78:1604-1613. [PMID: 34458980 DOI: 10.1111/biom.13531] [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: 08/05/2020] [Revised: 06/29/2021] [Accepted: 07/08/2021] [Indexed: 12/30/2022]
Abstract
We develop an envelope model for joint mean and covariance regression in the large p, small n setting. In contrast to existing envelope methods, which improve mean estimates by incorporating estimates of the covariance structure, we focus on identifying covariance heterogeneity by incorporating information about mean-level differences. We use a Monte Carlo EM algorithm to identify a low-dimensional subspace that explains differences in both means and covariances as a function of covariates, and then use MCMC to estimate the posterior uncertainty conditional on the inferred low-dimensional subspace. We demonstrate the utility of our model on a motivating application on the metabolomics of aging. We also provide R code that can be used to develop and test other generalizations of the response envelope model.
Collapse
Affiliation(s)
- Alexander M Franks
- Department of Statistics and Applied Probability, University of California Santa Barbara, Santa Barbara, California, USA
| |
Collapse
|
9
|
Zheng W, Li R, Zhou Y, Shi F, Song Y, Liao Y, Zhou F, Zheng X, Lv J, Li Q. Effect of dietary protein content shift on aging in elderly rats by comprehensive quantitative score and metabolomics analysis. Front Nutr 2022; 9:1051964. [DOI: 10.3389/fnut.2022.1051964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 10/19/2022] [Indexed: 11/06/2022] Open
Abstract
In the protein nutrition strategy of middle-aged and elderly people, some believe that low protein is good for health, while others believe high protein is good for health. Facing the contradictory situation, the following hypothesis is proposed. There is a process of change from lower to higher ratio of protein nutritional requirements that are good for health in the human body after about 50 years of age, and the age at which the switch occurs is around 65 years of age. Hence, in this study, 50, 25-month-old male rats were randomly divided into five groups: Control (basal diet), LP (low-protein diet with a 30% decrease in protein content compared to the basal diet), HP (high-protein diet with a 30% increase in protein content compared to the basal diet), Model 1 (switched from LP to HP feed at week 4), and Model 2 (switched from LP to HP feed at week 7). After a total of 10 weeks intervention, the liver and serum samples were examined for aging-related indicators, and a newly comprehensive quantitative score was generated using principal component analysis (PCA). The effects of the five protein nutritional modalities were quantified in descending order: Model 1 > HP > LP > Control > Model 2. Furthermore, the differential metabolites in serum and feces were determined by orthogonal partial least squares discriminant analysis, and 15 differential metabolites, significantly associated with protein intake, were identified by Spearman’s correlation analysis (p < 0.05). Among the fecal metabolites, 10 were positively correlated and 3 were negatively correlated. In the serum, tyrosine and lactate levels were positively correlated, and acetate levels were negatively correlated. MetaboAnalyst analysis identified that the metabolic pathways influenced by protein intake were mainly related to amino acid and carbohydrate metabolism. The results of metabolomic analysis elucidate the mechanisms underlying the preceding effects to some degree. These efforts not only contribute to a unified protein nutrition strategy but also positively impact the building of a wiser approach to protein nutrition, thereby helping middle-aged and older populations achieve healthy aging.
Collapse
|
10
|
Borges G, Criqui M, Harrington L. Tieing together loose ends: telomere instability in cancer and aging. Mol Oncol 2022; 16:3380-3396. [PMID: 35920280 PMCID: PMC9490142 DOI: 10.1002/1878-0261.13299] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 07/27/2022] [Accepted: 08/02/2022] [Indexed: 11/29/2022] Open
Abstract
Telomere maintenance is essential for maintaining genome integrity in both normal and cancer cells. Without functional telomeres, chromosomes lose their protective structure and undergo fusion and breakage events that drive further genome instability, including cell arrest or death. One means by which this loss can be overcome in stem cells and cancer cells is via re-addition of G-rich telomeric repeats by the telomerase reverse transcriptase (TERT). During aging of somatic tissues, however, insufficient telomerase expression leads to a proliferative arrest called replicative senescence, which is triggered when telomeres reach a critically short threshold that induces a DNA damage response. Cancer cells express telomerase but do not entirely escape telomere instability as they often possess short telomeres; hence there is often selection for genetic alterations in the TERT promoter that result in increased telomerase expression. In this review, we discuss our current understanding of the consequences of telomere instability in cancer and aging, and outline the opportunities and challenges that lie ahead in exploiting the reliance of cells on telomere maintenance for preserving genome stability.
Collapse
Affiliation(s)
- Gustavo Borges
- Molecular Biology Programme, Institute for Research in Immunology and CancerUniversity of MontrealQCCanada
| | - Mélanie Criqui
- Molecular Biology Programme, Institute for Research in Immunology and CancerUniversity of MontrealQCCanada
| | - Lea Harrington
- Molecular Biology Programme, Institute for Research in Immunology and CancerUniversity of MontrealQCCanada
- Departments of Medicine and Biochemistry and Molecular MedicineUniversity of MontrealQCCanada
| |
Collapse
|
11
|
Leonov A, Feldman R, Piano A, Arlia-Ciommo A, Junio JAB, Orfanos E, Tafakori T, Lutchman V, Mohammad K, Elsaser S, Orfali S, Rajen H, Titorenko VI. Diverse geroprotectors differently affect a mechanism linking cellular aging to cellular quiescence in budding yeast. Oncotarget 2022; 13:918-943. [PMID: 35937500 PMCID: PMC9348708 DOI: 10.18632/oncotarget.28256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 07/01/2022] [Indexed: 11/25/2022] Open
Affiliation(s)
- Anna Leonov
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Rachel Feldman
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Amanda Piano
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | | | | | - Emmanuel Orfanos
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Tala Tafakori
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Vicky Lutchman
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Karamat Mohammad
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Sarah Elsaser
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Sandra Orfali
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | - Harshvardhan Rajen
- Department of Biology, Concordia University, Montreal, Quebec H4B 1R6, Canada
| | | |
Collapse
|
12
|
Suo M, Rommelfanger MK, Chen Y, Amro EM, Han B, Chen Z, Szafranski K, Chakkarappan SR, Boehm BO, MacLean AL, Rudolph KL. Age-dependent effects of Igf2bp2 on gene regulation, function, and aging of hematopoietic stem cells in mice. Blood 2022; 139:2653-2665. [PMID: 35231105 PMCID: PMC11022928 DOI: 10.1182/blood.2021012197] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 02/10/2022] [Indexed: 11/20/2022] Open
Abstract
Increasing evidence links metabolism, protein synthesis, and growth signaling to impairments in the function of hematopoietic stem and progenitor cells (HSPCs) during aging. The Lin28b/Hmga2 pathway controls tissue development, and the postnatal downregulation of this pathway limits the self-renewal of adult vs fetal hematopoietic stem cells (HSCs). Igf2bp2 is an RNA binding protein downstream of Lin28b/Hmga2, which regulates messenger RNA stability and translation. The role of Igf2bp2 in HSC aging is unknown. In this study, an analysis of wild-type and Igf2bp2 knockout mice showed that Igf2bp2 regulates oxidative metabolism in HSPCs and the expression of metabolism, protein synthesis, and stemness-related genes in HSCs of young mice. Interestingly, Igf2bp2 expression and function strongly declined in aging HSCs. In young mice, Igf2bp2 deletion mimicked aging-related changes in HSCs, including changes in Igf2bp2 target gene expression and impairment of colony formation and repopulation capacity. In aged mice, Igf2bp2 gene status had no effect on these parameters in HSCs. Unexpectedly, Igf2bp2-deficient mice exhibited an amelioration of the aging-associated increase in HSCs and myeloid-skewed differentiation. The results suggest that Igf2bp2 controls mitochondrial metabolism, protein synthesis, growth, and stemness of young HSCs, which is necessary for full HSC function during young adult age. However, Igf2bp2 gene function is lost during aging, and it appears to contribute to HSC aging in 2 ways: the aging-related loss of Igf2bp2 gene function impairs the growth and repopulation capacity of aging HSCs, and the activity of Igf2bp2 at a young age contributes to aging-associated HSC expansion and myeloid skewing.
Collapse
Affiliation(s)
- Miaomiao Suo
- Leibniz Institute on Aging, Fritz Lipmann Institute (FLI), Jena, Germany
| | - Megan K. Rommelfanger
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA
| | - Yulin Chen
- Leibniz Institute on Aging, Fritz Lipmann Institute (FLI), Jena, Germany
| | - Elias Moris Amro
- Leibniz Institute on Aging, Fritz Lipmann Institute (FLI), Jena, Germany
| | - Bing Han
- Leibniz Institute on Aging, Fritz Lipmann Institute (FLI), Jena, Germany
| | - Zhiyang Chen
- Leibniz Institute on Aging, Fritz Lipmann Institute (FLI), Jena, Germany
| | - Karol Szafranski
- Leibniz Institute on Aging, Fritz Lipmann Institute (FLI), Jena, Germany
| | | | - Bernhard O. Boehm
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Singapore
| | - Adam L. MacLean
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA
| | - K. Lenhard Rudolph
- Leibniz Institute on Aging, Fritz Lipmann Institute (FLI), Jena, Germany
- Medical Faculty, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| |
Collapse
|
13
|
Sebastian C, Vong JSL, Mayekar MK, Tummala KS, Singh I. Editorial: Metabolism and Epigenetics. Front Genet 2022; 13:877538. [PMID: 35360874 PMCID: PMC8960136 DOI: 10.3389/fgene.2022.877538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 02/23/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Carlos Sebastian
- Department of Cell Biology, Physiology and Immunology, School of Biology, University of Barcelona, Barcelona, Spain
- Institute of Biomedicine of the University of Barcelona (IBUB), Barcelona, Spain
| | - Joaquim S. L. Vong
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China
| | | | - Krishna S. Tummala
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, , United States
| | - Indrabahadur Singh
- Emmy Noether Research Group Epigenetic Machineries and Cancer, Division of Chronic Inflammation and Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
- *Correspondence: Indrabahadur Singh,
| |
Collapse
|
14
|
Montano M, Oursler KK, Xu K, Sun YV, Marconi VC. Biological ageing with HIV infection: evaluating the geroscience hypothesis. THE LANCET. HEALTHY LONGEVITY 2022; 3:e194-e205. [PMID: 36092375 PMCID: PMC9454292 DOI: 10.1016/s2666-7568(21)00278-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Although people with HIV are living longer, as they age they remain disproportionately burdened with multimorbidity that is exacerbated in resource-poor settings. The geroscience hypothesis postulates that a discrete set of between five and ten hallmarks of biological ageing drive multimorbidity, but these processes have not been systematically examined in the context of people with HIV. We examine four major hallmarks of ageing (macromolecular damage, senescence, inflammation, and stem-cell dysfunction) as gerodrivers in the context of people with HIV. As a counterbalance, we introduce healthy ageing, physiological reserve, intrinsic capacity, and resilience as promoters of geroprotection that counteract gerodrivers. We discuss emerging geroscience-based diagnostic biomarkers and therapeutic strategies, and provide examples based on recent advances in cellular senescence, and other, non-pharmacological approaches. Finally, we present a conceptual model of biological ageing in the general population and in people with HIV that integrates gerodrivers and geroprotectors as modulators of homoeostatic reserves and organ function over the lifecourse.
Collapse
|
15
|
Mendelsohn AR, Larrick JW. Stem Cell Rejuvenation by Restoration of Youthful Metabolic Compartmentalization. Rejuvenation Res 2021; 24:470-474. [PMID: 34846176 DOI: 10.1089/rej.2021.0076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Stem cell dysfunction is a hallmark of aging. Much recent study suggests that epigenetic changes play a critical role in the loss of stem cell function with age. However, the underlying mechanisms require elucidation. A recent report describes a process by which mild mitochondrial stress associated with aging causes lysosomal-mediated decreases in CiC, the mitochondrial citrate transporter, in bone marrow-derived mesenchymal stem cells (MSCs). This, in turn, results in a deficit of acetyl-CoA in the nucleus and hypoacetylation of histones. The altered epigenome results in skewered stem cell differentiation favoring adipogenesis and disfavoring osteogenesis, which is problematic given the role the MSCs play in maintaining the integrity of bone tissue. Restoration of nuclear acetyl-CoA by either ectopic expression of CiC or acetate supplementation of MSCs in culture rejuvenates the MSC, restoring the potential to efficiently differentiate along the osteogenic lineage. Citrate, which has recently been reported to extend lifespan in Drosophila, chemically incorporates acetyl-CoA and may prove useful to restore cytoplasmic and nuclear acetyl-CoA levels. The general applicability of the CiC defect in old cells, particularly stem cells, should be established.
Collapse
Affiliation(s)
- Andrew R Mendelsohn
- Panorama Research Institute, Sunnyvale, California, USA.,Regenerative Sciences Institute, Sunnyvale, California, USA
| | - James W Larrick
- Panorama Research Institute, Sunnyvale, California, USA.,Regenerative Sciences Institute, Sunnyvale, California, USA
| |
Collapse
|
16
|
Li L, Qiu Y, Miao M, Liu Z, Li W, Zhu Y, Wang Q. Reduction of Tet2 exacerbates early stage Alzheimer's pathology and cognitive impairments in 2×Tg-AD mice. Hum Mol Genet 2021; 29:1833-1852. [PMID: 31943063 DOI: 10.1093/hmg/ddz282] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 10/20/2019] [Accepted: 11/19/2019] [Indexed: 12/29/2022] Open
Abstract
Abnormal modification of 5-hydroxymethylcytosine (5hmC) is closely related to the occurrence of Alzheimer's disease (AD). However, the role of 5hmC and its writers, ten-eleven translocation (Tet) proteins, in regulating the pathogenesis of AD remains largely unknown. We detected a significant decrease in 5hmC and Tet2 levels in the hippocampus of aged APPswe/PSEN1 double-transgenic (2×Tg-AD) mice that coincides with abundant amyloid-β (Aβ) plaque accumulation. On this basis, we examined the reduction of Tet2 expression in the hippocampus at early disease stages, which caused a decline of 5hmC levels and led young 2×Tg-AD mice to present with advanced stages of AD-related pathological hallmarks, including Aβ accumulation, GFAP-positive astrogliosis and Iba1-positive microglia overgrowth as well as the overproduction of pro-inflammatory factors. Additionally, the loss of Tet2 in the 2×Tg-AD mice at 5 months of age accelerated hippocampal-dependent learning and memory impairments compared to age-matched control 2×Tg-AD mice. In contrast, restoring Tet2 expression in adult neural stem cells isolated from aged 2×Tg-AD mice hippocampi increased 5hmC levels and increased their regenerative capacity, suggesting that Tet2 might be an exciting target for rejuvenating the brain during aging and AD. Further, hippocampal RNA sequencing data revealed that the expression of altered genes identified in both Tet2 knockdown and control 2×Tg-AD mice was significantly associated with inflammation response. Finally, we demonstrated that Tet2-mediated 5hmC epigenetic modifications regulate AD pathology by interacting with HDAC1. These results suggest a combined approach for the regulation and treatment of AD-related memory impairment and cognitive symptoms by increasing Tet2 via HDAC1 suppression.
Collapse
Affiliation(s)
- Liping Li
- Ningbo Key Laboratory of Behavioral Neuroscience, Department of Physiology and Pharmacology, Ningbo University School of Medicine, Ningbo 315211, China.,Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University School of Medicine, Ningbo 315211, China
| | - Yisha Qiu
- Ningbo Key Laboratory of Behavioral Neuroscience, Department of Physiology and Pharmacology, Ningbo University School of Medicine, Ningbo 315211, China.,Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University School of Medicine, Ningbo 315211, China
| | - Miao Miao
- Ningbo Key Laboratory of Behavioral Neuroscience, Department of Physiology and Pharmacology, Ningbo University School of Medicine, Ningbo 315211, China.,Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University School of Medicine, Ningbo 315211, China
| | - Zhitao Liu
- Faculty of Sports Science, Ningbo University, Ningbo 315211, China
| | - Wanyi Li
- Faculty of Sports Science, Ningbo University, Ningbo 315211, China
| | - Yiyi Zhu
- Ningbo Key Laboratory of Behavioral Neuroscience, Department of Physiology and Pharmacology, Ningbo University School of Medicine, Ningbo 315211, China.,Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University School of Medicine, Ningbo 315211, China
| | - Qinwen Wang
- Ningbo Key Laboratory of Behavioral Neuroscience, Department of Physiology and Pharmacology, Ningbo University School of Medicine, Ningbo 315211, China.,Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University School of Medicine, Ningbo 315211, China
| |
Collapse
|
17
|
Koester J, Miroshnikova YA, Ghatak S, Chacón-Martínez CA, Morgner J, Li X, Atanassov I, Altmüller J, Birk DE, Koch M, Bloch W, Bartusel M, Niessen CM, Rada-Iglesias A, Wickström SA. Niche stiffening compromises hair follicle stem cell potential during ageing by reducing bivalent promoter accessibility. Nat Cell Biol 2021; 23:771-781. [PMID: 34239060 DOI: 10.1038/s41556-021-00705-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 05/27/2021] [Indexed: 02/06/2023]
Abstract
Tissue turnover requires activation and lineage commitment of tissue-resident stem cells (SCs). These processes are impacted by ageing, but the mechanisms remain unclear. Here, we addressed the mechanisms of ageing in murine hair follicle SCs (HFSCs) and observed a widespread reduction in chromatin accessibility in aged HFSCs, particularly at key self-renewal and differentiation genes, characterized by bivalent promoters occupied by active and repressive chromatin marks. Consistent with this, aged HFSCs showed reduced ability to activate bivalent genes for efficient self-renewal and differentiation. These defects were niche dependent as the transplantation of aged HFSCs into young recipients or synthetic niches restored SC functions. Mechanistically, the aged HFSC niche displayed widespread alterations in extracellular matrix composition and mechanics, resulting in mechanical stress and concomitant transcriptional repression to silence promoters. As a consequence, increasing basement membrane stiffness recapitulated age-related SC changes. These data identify niche mechanics as a central regulator of chromatin state, which, when altered, leads to age-dependent SC exhaustion.
Collapse
Affiliation(s)
- Janis Koester
- Max Planck Institute for Biology of Ageing, Cologne, Germany
- Cologne Excellence Cluster for Stress Responses in Ageing-associated diseases (CECAD), University of Cologne, Cologne, Germany
| | - Yekaterina A Miroshnikova
- Max Planck Institute for Biology of Ageing, Cologne, Germany
- Cologne Excellence Cluster for Stress Responses in Ageing-associated diseases (CECAD), University of Cologne, Cologne, Germany
- Helsinki Institute of Life Science, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland
- Wihuri Research Institute, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Sushmita Ghatak
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | | | - Jessica Morgner
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Xinping Li
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Ilian Atanassov
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Janine Altmüller
- Cologne Center for Genomics, University of Cologne, Cologne, Germany
| | - David E Birk
- Department of Molecular Pharmacology & Physiology, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
| | - Manuel Koch
- Institute for Dental Research and Oral Musculoskeletal Research, Center for Biochemistry, University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Wilhelm Bloch
- Molecular and Cellular Sport Medicine, German Sport University Cologne, Cologne, Germany
| | - Michaela Bartusel
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Carien M Niessen
- Cologne Excellence Cluster for Stress Responses in Ageing-associated diseases (CECAD), University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
- Department of Dermatology, Center for Molecular Medicine, University of Cologne, Cologne, Germany
| | - Alvaro Rada-Iglesias
- Cologne Excellence Cluster for Stress Responses in Ageing-associated diseases (CECAD), University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
- Institute of Biomedicine and Biotechnology of Cantabria (IBBTEC), University of Cantabria/CSIC, Cantabria, Spain
| | - Sara A Wickström
- Max Planck Institute for Biology of Ageing, Cologne, Germany.
- Cologne Excellence Cluster for Stress Responses in Ageing-associated diseases (CECAD), University of Cologne, Cologne, Germany.
- Helsinki Institute of Life Science, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland.
- Wihuri Research Institute, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland.
- Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
| |
Collapse
|
18
|
Guerrero J, Häckel S, Croft AS, Albers CE, Gantenbein B. The effects of 3D culture on the expansion and maintenance of nucleus pulposus progenitor cell multipotency. JOR Spine 2021; 4:e1131. [PMID: 33778405 PMCID: PMC7984018 DOI: 10.1002/jsp2.1131] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 10/29/2020] [Accepted: 11/04/2020] [Indexed: 02/06/2023] Open
Abstract
INTRODUCTION Low back pain (LBP) is a global health concern. Increasing evidence implicates intervertebral disk (IVD) degeneration as a major contributor. In this respect, tissue-specific progenitors may play a crucial role in tissue regeneration, as these cells are perfectly adapted to their niche. Recently, a novel progenitor cell population was described in the nucleus pulposus (NP) that is positive for Tie2 marker. These cells have self-renewal capacity and in vitro multipotency potential. However, extremely low numbers of the NP progenitors limit the feasibility of cell therapy strategies. OBJECTIVE Here, we studied the influence of the culture method and of the microenvironment on the proliferation rate and the differentiation potential of human NP progenitors in vitro. METHOD Cells were obtained from human NP tissue from trauma patients. Briefly, the NP tissue cells were cultured in two-dimensional (2D) (monolayer) or three-dimensional (3D) (alginate beads) conditions. After 1 week, cells from 2D or 3D culture were expanded on fibronectin-coated flasks. Subsequently, expanded NP cells were then characterized by cytometry and tri-lineage differentiation, which was analyzed by qPCR and histology. Moreover, experiments using Tie2+ and Tie2- NP cells were also performed. RESULTS The present study aims to demonstrate that 3D expansion of NP cells better preserves the Tie2+ cell populations and increases the chondrogenic and osteogenic differentiation potential compared to 2D expansion. Moreover, the cell sorting experiments reveal that only Tie2+ cells were able to maintain the pluripotent gene expression if cultured in 3D within alginate beads. Therefore, our results highly suggest that the maintenance of the cell's multipotency is mainly, but not exclusively, due to the higher presence of Tie2+ cells due to 3D culture. CONCLUSION This project not only might have a scientific impact by evaluating the influence of a two-step expansion protocol on the functionality of NP progenitors, but it could also lead to an innovative clinical approach.
Collapse
Affiliation(s)
- Julien Guerrero
- Tissue Engineering for Orthopaedics & Mechanobiology, Department for BioMedical Research (DBMR) of the Faculty of Medicine of the University of BernUniversity of BernSwitzerland
| | - Sonja Häckel
- Department of Orthopaedic Surgery & Traumatology, InselspitalBern University HospitalBernSwitzerland
| | - Andreas S. Croft
- Tissue Engineering for Orthopaedics & Mechanobiology, Department for BioMedical Research (DBMR) of the Faculty of Medicine of the University of BernUniversity of BernSwitzerland
| | - Christoph E. Albers
- Department of Orthopaedic Surgery & Traumatology, InselspitalBern University HospitalBernSwitzerland
| | - Benjamin Gantenbein
- Tissue Engineering for Orthopaedics & Mechanobiology, Department for BioMedical Research (DBMR) of the Faculty of Medicine of the University of BernUniversity of BernSwitzerland
- Department of Orthopaedic Surgery & Traumatology, InselspitalBern University HospitalBernSwitzerland
| |
Collapse
|
19
|
Abstract
Quiescence is a cellular state in which a cell remains out of the cell cycle but retains the capacity to divide. The unique ability of adult stem cells to maintain quiescence is crucial for life-long tissue homeostasis and regenerative capacity. Quiescence has long been viewed as an inactive state but recent studies have shown that it is in fact an actively regulated process and that adult stem cells are highly reactive to extrinsic stimuli. This has fuelled hopes of boosting the reactivation potential of adult stem cells to improve tissue function during ageing. In this Review, we provide a perspective of the quiescent state and discuss how quiescent adult stem cells transition into the cell cycle. We also discuss current challenges in the field, highlighting recent technical advances that could help overcome some of these challenges.
Collapse
Affiliation(s)
- Noelia Urbán
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter Campus (VBC), Dr. Bohr Gasse 3, 1030 Vienna, Austria
| | - Tom H Cheung
- Division of Life Science, Center for Stem Cell Research, Center of Systems Biology and Human Health, State Key Laboratory of Molecular Neuroscience, and Molecular Neuroscience Center, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
- Hong Kong Center for Neurodegenerative Diseases, Hong Kong Science Park, Hong Kong, China
- Guangdong Provincial Key Laboratory of Brain Science, Disease and Drug Development, The Hong Kong University of Science and Technology Shenzhen Research Institute, Shenzhen-Hong Kong Institute of Brain Science, Shenzhen, Guangdong 518057, China
| |
Collapse
|
20
|
Cairns G, Thumiah-Mootoo M, Burelle Y, Khacho M. Mitophagy: A New Player in Stem Cell Biology. BIOLOGY 2020; 9:E481. [PMID: 33352783 PMCID: PMC7766552 DOI: 10.3390/biology9120481] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/02/2020] [Accepted: 12/03/2020] [Indexed: 02/06/2023]
Abstract
The fundamental importance of functional mitochondria in the survival of most eukaryotic cells, through regulation of bioenergetics, cell death, calcium dynamics and reactive oxygen species (ROS) generation, is undisputed. However, with new avenues of research in stem cell biology these organelles have now emerged as signaling entities, actively involved in many aspects of stem cell functions, including self-renewal, commitment and differentiation. With this recent knowledge, it becomes evident that regulatory pathways that would ensure the maintenance of mitochondria with state-specific characteristics and the selective removal of organelles with sub-optimal functions must play a pivotal role in stem cells. As such, mitophagy, as an essential mitochondrial quality control mechanism, is beginning to gain appreciation within the stem cell field. Here we review and discuss recent advances in our knowledge pertaining to the roles of mitophagy in stem cell functions and the potential contributions of this specific quality control process on to the progression of aging and diseases.
Collapse
Affiliation(s)
- George Cairns
- Interdisciplinary School of Health Sciences, Faculty of Health Sciences, University of Ottawa, Ottawa, ON K1N 7K4, Canada;
| | - Madhavee Thumiah-Mootoo
- Department of Cellular & Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada;
| | - Yan Burelle
- Interdisciplinary School of Health Sciences, Faculty of Health Sciences, University of Ottawa, Ottawa, ON K1N 7K4, Canada;
- Department of Cellular & Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada;
| | - Mireille Khacho
- Center for Neuromuscular Disease, Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, Ottawa Institute of Systems Biology (OISB), University of Ottawa, Ottawa, ON K1H 8M5, Canada
| |
Collapse
|
21
|
Al Zouabi L, Bardin AJ. Stem Cell DNA Damage and Genome Mutation in the Context of Aging and Cancer Initiation. Cold Spring Harb Perspect Biol 2020; 12:cshperspect.a036210. [PMID: 31932318 DOI: 10.1101/cshperspect.a036210] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Adult stem cells fuel tissue homeostasis and regeneration through their unique ability to self-renew and differentiate into specialized cells. Thus, their DNA provides instructions that impact the tissue as a whole. Since DNA is not an inert molecule, but rather dynamic, interacting with a myriad of chemical and physical factors, it encounters damage from both endogenous and exogenous sources. Damage to DNA introduces deviations from its normal intact structure and, if left unrepaired, may result in a genetic mutation. In turn, mutant genomes of stem and progenitor cells are inherited in cells of the lineage, thus eroding the genetic information that maintains homeostasis of the somatic cell population. Errors arising in stem and progenitor cells will have a substantially larger impact on the tissue in which they reside than errors occurring in postmitotic differentiated cells. Therefore, maintaining the integrity of genomic DNA within our stem cells is essential to protect the instructions necessary for rebuilding healthy tissues during homeostatic renewal. In this review, we will first discuss DNA damage arising in stem cells and cell- and tissue-intrinsic mechanisms that protect against harmful effects of this damage. Secondly, we will examine how erroneous DNA repair and persistent DNA damage in stem and progenitor cells impact stem cells and tissues in the context of cancer initiation and aging. Finally, we will discuss the use of invertebrate and vertebrate model systems to address unanswered questions on the role that DNA damage and mutation may play in aging and precancerous conditions.
Collapse
Affiliation(s)
- Lara Al Zouabi
- Institut Curie, PSL Research University, CNRS UMR 3215, INSERM U934, Stem Cells and Tissue Homeostasis Group, 75248 Paris, France.,Sorbonne Universités, UPMC University, Paris 6, France
| | - Allison J Bardin
- Institut Curie, PSL Research University, CNRS UMR 3215, INSERM U934, Stem Cells and Tissue Homeostasis Group, 75248 Paris, France.,Sorbonne Universités, UPMC University, Paris 6, France
| |
Collapse
|
22
|
Abstract
Individuals that maintain healthy skeletal tissue tend to live healthier, happier lives as proper muscle function enables maintenance of independence and actuation of autonomy. The onset of skeletal muscle decline begins around the age of 30, and muscle atrophy is associated with a number of serious morbidities and mortalities. Satellite cells are responsible for regeneration of skeletal muscle and enter a reversible non-dividing state of quiescence under homeostatic conditions. In response to injury, satellite cells are able to activate and re-enter the cell cycle, creating new cells to repair and create nascent muscle fibres while preserving a small population that can return to quiescence for future regenerative demands. However, in aged muscle, satellite cells that experience prolonged quiescence will undergo programmed cellular senescence, an irreversible non-dividing state that handicaps the regenerative capabilities of muscle. This review examines how periodic activation and cycling of satellite cells through exercise can mitigate senescence acquisition and myogenic decline.
Collapse
Affiliation(s)
- William Chen
- Sprott Centre for Stem Cell Research, Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada K1H 8L6.,Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada K1H 8M5
| | - David Datzkiw
- Sprott Centre for Stem Cell Research, Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada K1H 8L6.,Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada K1H 8M5
| | - Michael A Rudnicki
- Sprott Centre for Stem Cell Research, Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada K1H 8L6.,Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada K1H 8M5
| |
Collapse
|
23
|
Morganti C, Bonora M, Marchi S, Ferroni L, Gardin C, Wieckowski MR, Giorgi C, Pinton P, Zavan B. Citrate Mediates Crosstalk between Mitochondria and the Nucleus to Promote Human Mesenchymal Stem Cell In Vitro Osteogenesis. Cells 2020; 9:cells9041034. [PMID: 32326298 PMCID: PMC7226543 DOI: 10.3390/cells9041034] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 04/07/2020] [Accepted: 04/19/2020] [Indexed: 12/15/2022] Open
Abstract
Citrate, generated in the mitochondria, is a key metabolite that might link metabolism with signaling, chromatin structure and transcription to orchestrate mesenchymal stem cells (MSCs) fate determination. Based on a detailed morphological analysis of 3D reconstruction of mitochondria and nuclei in single cells, we identified contact sites between these organelles that drastically increase in volume and number during the early stage of mesenchymal stem cell differentiation. These contact sites create a microdomain that facilitates exchange of signals from mitochondria to the nucleus. Interestingly, we found that the citrate derived from mitochondria is necessary for osteogenic lineage determination. Indeed, inhibition of the citrate transporter system dramatically affected osteogenesis, reduced citrate levels that could be converted in α-ketoglutarate, and consequently affected epigenetic marker H3K9me3 associated with the osteogenesis differentiation process. These findings highlight that mitochondrial metabolites play key regulatory roles in the MSCs differentiation process. Further in-depth investigation is needed to provide novel therapeutic strategies in the field of regenerative medicine.
Collapse
Affiliation(s)
- Claudia Morganti
- Department of Medical Sciences, University of Ferrara, 44121 Ferrara, Italy; (C.M.); (M.B.); (S.M.); (C.G.)
- Laboratorio per le Tecnologie delle Terapie Avanzate (LTTA), University of Ferrara, 44121 Ferrara, Italy
| | - Massimo Bonora
- Department of Medical Sciences, University of Ferrara, 44121 Ferrara, Italy; (C.M.); (M.B.); (S.M.); (C.G.)
- Laboratorio per le Tecnologie delle Terapie Avanzate (LTTA), University of Ferrara, 44121 Ferrara, Italy
| | - Saverio Marchi
- Department of Medical Sciences, University of Ferrara, 44121 Ferrara, Italy; (C.M.); (M.B.); (S.M.); (C.G.)
- Laboratorio per le Tecnologie delle Terapie Avanzate (LTTA), University of Ferrara, 44121 Ferrara, Italy
| | - Letizia Ferroni
- Maria Cecilia Hospital, GVM Care & Research, Via Corriera 1, Cotignola, 48033 Ravenna, Italy; (L.F.); (C.G.)
| | - Chiara Gardin
- Maria Cecilia Hospital, GVM Care & Research, Via Corriera 1, Cotignola, 48033 Ravenna, Italy; (L.F.); (C.G.)
| | - Mariusz R. Wieckowski
- Laboratory of Mitochondrial Biology and Metabolism, Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland;
| | - Carlotta Giorgi
- Department of Medical Sciences, University of Ferrara, 44121 Ferrara, Italy; (C.M.); (M.B.); (S.M.); (C.G.)
- Laboratorio per le Tecnologie delle Terapie Avanzate (LTTA), University of Ferrara, 44121 Ferrara, Italy
| | - Paolo Pinton
- Department of Medical Sciences, University of Ferrara, 44121 Ferrara, Italy; (C.M.); (M.B.); (S.M.); (C.G.)
- Laboratorio per le Tecnologie delle Terapie Avanzate (LTTA), University of Ferrara, 44121 Ferrara, Italy
- Maria Cecilia Hospital, GVM Care & Research, Via Corriera 1, Cotignola, 48033 Ravenna, Italy; (L.F.); (C.G.)
- Correspondence: (P.P.); (B.Z.)
| | - Barbara Zavan
- Maria Cecilia Hospital, GVM Care & Research, Via Corriera 1, Cotignola, 48033 Ravenna, Italy; (L.F.); (C.G.)
- Department of Morphology, Surgery and Experimental Medicine, Section of Pathology, Oncology, University of Ferrara, 44121 Ferrara, Italy
- Correspondence: (P.P.); (B.Z.)
| |
Collapse
|
24
|
Criqui M, Qamra A, Chu TW, Sharma M, Tsao J, Henry DA, Barsyte-Lovejoy D, Arrowsmith CH, Winegarden N, Lupien M, Harrington L. Telomere dysfunction cooperates with epigenetic alterations to impair murine embryonic stem cell fate commitment. eLife 2020; 9:47333. [PMID: 32297856 PMCID: PMC7192583 DOI: 10.7554/elife.47333] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 04/06/2020] [Indexed: 12/11/2022] Open
Abstract
The precise relationship between epigenetic alterations and telomere dysfunction is still an extant question. Previously, we showed that eroded telomeres lead to differentiation instability in murine embryonic stem cells (mESCs) via DNA hypomethylation at pluripotency-factor promoters. Here, we uncovered that telomerase reverse transcriptase null (Tert-/-) mESCs exhibit genome-wide alterations in chromatin accessibility and gene expression during differentiation. These changes were accompanied by an increase of H3K27me3 globally, an altered chromatin landscape at the Pou5f1/Oct4 promoter, and a refractory response to differentiation cues. Inhibition of the Polycomb Repressive Complex 2 (PRC2), an H3K27 tri-methyltransferase, exacerbated the impairment in differentiation and pluripotency gene repression in Tert-/-mESCs but not wild-type mESCs, whereas inhibition of H3K27me3 demethylation led to a partial rescue of the Tert-/- phenotype. These data reveal a new interdependent relationship between H3K27me3 and telomere integrity in stem cell lineage commitment that may have implications in aging and cancer.
Collapse
Affiliation(s)
- Mélanie Criqui
- Institut de Recherche en Immunologie et Cancérologie (IRIC), Département de biologie moléculaire, Faculté de Médecine, Université de Montréal, Montréal, Canada
| | - Aditi Qamra
- Princess Margaret Cancer Centre, University Health Network, Toronto, Canada
| | - Tsz Wai Chu
- Institut de Recherche en Immunologie et Cancérologie (IRIC), Département de biologie moléculaire, Faculté de Médecine, Université de Montréal, Montréal, Canada
| | - Monika Sharma
- Princess Margaret Genomics Centre, Princess Margaret Cancer Centre, University Health Network, Toronto, Canada
| | - Julissa Tsao
- Princess Margaret Genomics Centre, Princess Margaret Cancer Centre, University Health Network, Toronto, Canada
| | - Danielle A Henry
- Institut de Recherche en Immunologie et Cancérologie (IRIC), Département de biologie moléculaire, Faculté de Médecine, Université de Montréal, Montréal, Canada
| | - Dalia Barsyte-Lovejoy
- Structural Genomics Consortium, Princess Margaret Cancer Centre, University of Toronto, Department of Medical Biophysics, Toronto, Canada
| | - Cheryl H Arrowsmith
- Structural Genomics Consortium, Princess Margaret Cancer Centre, University of Toronto, Department of Medical Biophysics, Toronto, Canada
| | - Neil Winegarden
- Princess Margaret Genomics Centre, Princess Margaret Cancer Centre, University Health Network, Toronto, Canada
| | - Mathieu Lupien
- Princess Margaret Cancer Centre, University Health Network, Toronto, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Canada
| | - Lea Harrington
- Institut de Recherche en Immunologie et Cancérologie (IRIC), Département de biologie moléculaire, Faculté de Médecine, Université de Montréal, Montréal, Canada
| |
Collapse
|
25
|
Abstract
Aging manifests with architectural alteration and functional decline of multiple organs throughout an organism. In mammals, aged skin is accompanied by a marked reduction in hair cycling and appearance of bald patches, leading researchers to propose that hair follicle stem cells (HFSCs) are either lost, differentiate, or change to an epidermal fate during aging. Here, we employed single-cell RNA-sequencing to interrogate aging-related changes in the HFSCs. Surprisingly, although numbers declined, aging HFSCs were present, maintained their identity, and showed no overt signs of shifting to an epidermal fate. However, they did exhibit prevalent transcriptional changes particularly in extracellular matrix genes, and this was accompanied by profound structural perturbations in the aging SC niche. Moreover, marked age-related changes occurred in many nonepithelial cell types, including resident immune cells, sensory neurons, and arrector pili muscles. Each of these SC niche components has been shown to influence HF regeneration. When we performed skin injuries that are known to mobilize young HFSCs to exit their niche and regenerate HFs, we discovered that aged skin is defective at doing so. Interestingly, however, in transplantation assays in vivo, aged HFSCs regenerated HFs when supported with young dermis, while young HFSCs failed to regenerate HFs when combined with aged dermis. Together, our findings highlight the importance of SC:niche interactions and favor a model where youthfulness of the niche microenvironment plays a dominant role in dictating the properties of its SCs and tissue health and fitness.
Collapse
|
26
|
Müthel S, Tursun B. Epigenetic chaperoning of aging. Aging (Albany NY) 2020; 12:1044-1046. [PMID: 31991401 PMCID: PMC7053630 DOI: 10.18632/aging.102808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 01/23/2020] [Indexed: 11/30/2022]
Affiliation(s)
- Stefanie Müthel
- Berlin Institute of Medical Systems Biology, 10115 Berlin, Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany
| | - Baris Tursun
- Berlin Institute of Medical Systems Biology, 10115 Berlin, Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany
| |
Collapse
|
27
|
Gervais L, van den Beek M, Josserand M, Sallé J, Stefanutti M, Perdigoto CN, Skorski P, Mazouni K, Marshall OJ, Brand AH, Schweisguth F, Bardin AJ. Stem Cell Proliferation Is Kept in Check by the Chromatin Regulators Kismet/CHD7/CHD8 and Trr/MLL3/4. Dev Cell 2020; 49:556-573.e6. [PMID: 31112698 PMCID: PMC6547167 DOI: 10.1016/j.devcel.2019.04.033] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 03/15/2019] [Accepted: 04/18/2019] [Indexed: 12/13/2022]
Abstract
Chromatin remodeling accompanies differentiation, however, its role in self-renewal is less well understood. We report that in Drosophila, the chromatin remodeler Kismet/CHD7/CHD8 limits intestinal stem cell (ISC) number and proliferation without affecting differentiation. Stem-cell-specific whole-genome profiling of Kismet revealed its enrichment at transcriptionally active regions bound by RNA polymerase II and Brahma, its recruitment to the transcription start site of activated genes and developmental enhancers and its depletion from regions bound by Polycomb, Histone H1, and heterochromatin Protein 1. We demonstrate that the Trithorax-related/MLL3/4 chromatin modifier regulates ISC proliferation, colocalizes extensively with Kismet throughout the ISC genome, and co-regulates genes in ISCs, including Cbl, a negative regulator of Epidermal Growth Factor Receptor (EGFR). Loss of kismet or trr leads to elevated levels of EGFR protein and signaling, thereby promoting ISC self-renewal. We propose that Kismet with Trr establishes a chromatin state that limits EGFR proliferative signaling, preventing tumor-like stem cell overgrowths. Chromatin modifiers Kismet and Trr limit intestinal stem cell proliferation Kismet and Trr colocalize at transcriptionally active regions and co-regulate genes EGFR negative regulator Cbl is a target gene of Kismet and Trr Kismet and Trr limit EGFR signaling in ISCs, preventing tumor-like ISC accumulation
Collapse
Affiliation(s)
- Louis Gervais
- Institut Curie, PSL Research University, CNRS UMR 3215, INSERM U934, Stem Cells and Tissue Homeostasis Group, Paris, France; Sorbonne Universités, UPMC Univ Paris 6, Paris, France.
| | - Marius van den Beek
- Institut Curie, PSL Research University, CNRS UMR 3215, INSERM U934, Stem Cells and Tissue Homeostasis Group, Paris, France; Sorbonne Universités, UPMC Univ Paris 6, Paris, France
| | - Manon Josserand
- Institut Curie, PSL Research University, CNRS UMR 3215, INSERM U934, Stem Cells and Tissue Homeostasis Group, Paris, France; Sorbonne Universités, UPMC Univ Paris 6, Paris, France
| | - Jérémy Sallé
- Institut Curie, PSL Research University, CNRS UMR 3215, INSERM U934, Stem Cells and Tissue Homeostasis Group, Paris, France; Sorbonne Universités, UPMC Univ Paris 6, Paris, France
| | - Marine Stefanutti
- Institut Curie, PSL Research University, CNRS UMR 3215, INSERM U934, Stem Cells and Tissue Homeostasis Group, Paris, France; Sorbonne Universités, UPMC Univ Paris 6, Paris, France
| | - Carolina N Perdigoto
- Institut Curie, PSL Research University, CNRS UMR 3215, INSERM U934, Stem Cells and Tissue Homeostasis Group, Paris, France; Sorbonne Universités, UPMC Univ Paris 6, Paris, France
| | - Patricia Skorski
- Institut Curie, PSL Research University, CNRS UMR 3215, INSERM U934, Stem Cells and Tissue Homeostasis Group, Paris, France; Sorbonne Universités, UPMC Univ Paris 6, Paris, France
| | - Khallil Mazouni
- Institut Pasteur, Department of Developmental and Stem Cell Biology, Paris 75015, France; CNRS, URA2578, Rue du Dr Roux, Paris 75015, France
| | - Owen J Marshall
- The Gurdon Institute and Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 1QN, UK; Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool Street Hobart, Tasmania, 7000, Australia
| | - Andrea H Brand
- The Gurdon Institute and Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 1QN, UK
| | - François Schweisguth
- Institut Pasteur, Department of Developmental and Stem Cell Biology, Paris 75015, France; CNRS, URA2578, Rue du Dr Roux, Paris 75015, France
| | - Allison J Bardin
- Institut Curie, PSL Research University, CNRS UMR 3215, INSERM U934, Stem Cells and Tissue Homeostasis Group, Paris, France; Sorbonne Universités, UPMC Univ Paris 6, Paris, France.
| |
Collapse
|
28
|
De D, Karmakar P, Bhattacharya D. Stem Cell Aging and Regenerative Medicine. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1326:11-37. [PMID: 32910426 DOI: 10.1007/5584_2020_577] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Stem cells are a promising source for regenerative medicine to cure a plethora of diseases that are currently treated based on either palliative or symptomatic relief or by preventing their onset and progression. Aging-associated degenerative changes in stem cells, stem cell niches, and signaling pathways bring a step by step decline in the regenerative and functional potential of tissues. Clinical studies and experiments on model organisms have pointed out checkpoints that aging will inevitably impose on stem cell aiming for transplantation and hence questions are raised about the age of the donor. In the following discourse, we review the fundamental molecular pathways that are implicated in stem cell aging and the current progress in tissue engineering and transplantation of each type of stem cells in regenerative medicine. We further focus on the consequences of stem cell aging on their clinical uses and the development of novel strategies to bypass those pitfalls and improve tissue replenishment.
Collapse
Affiliation(s)
- Debojyoti De
- Department of Life science and Biotechnology, Jadavpur University, Kolkata, India
| | - Parimal Karmakar
- Department of Life science and Biotechnology, Jadavpur University, Kolkata, India
| | | |
Collapse
|
29
|
Imai A, Yamashita A, Ota MS. High-fat diet increases labial groove formation in maxillary incisors and is related to aging in C57BL/6 mice. J Oral Biosci 2019; 62:58-63. [PMID: 31862385 DOI: 10.1016/j.job.2019.12.003] [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: 10/24/2019] [Revised: 12/04/2019] [Accepted: 12/04/2019] [Indexed: 10/25/2022]
Abstract
OBJECTIVES The aim of this study was to explore the relationship between the consumption of a high-fat diet and aging-dependent formation of maxillary incisor grooves in C57BL/6 mice, and to identify putative maxillary incisor groove-related genes. METHODS We fed 2-month-old and 16-month-old C57BL/6 mice on either a chow diet or a high-fat diet for three months and observed changes in maxillary incisor grooves. We examined tissue sections of the maxillary incisors with grooves and carried out transcriptome analysis of the apical tissue fragments of maxillary incisors with/without grooves. RESULTS Consumption of a high-fat diet for three months resulted in significant increases in both body weight and the number of incisor grooves. Both the number and frequency of incisor grooves increased in an age-dependent manner from 26 to 28 months, during which time an additional groove appeared. There was abnormal differentiation and apoptosis of ameloblasts on the labial surface at the grooves of the maxillary incisors. Transcriptome analysis identified 23 genes as being specific to 24-month-old mice; these included several genes related to apoptosis and cell differentiation. CONCLUSIONS The study findings indicate that, in C57BL/6 mice, consumption of a high-fat diet increases labial groove formation in maxillary incisors, which is related to aging of the tissue stem cells in the apical root end of the teeth.
Collapse
Affiliation(s)
- Atsuko Imai
- The Division of Clinical Nutrition, Department of Food and Nutrition, Japan Women's University, Bunkyo-ku, Tokyo, Japan
| | - Atsuko Yamashita
- Laboratory of Anatomy and Physiology, Department of Food and Nutrition, Japan Women's University, Bunkyo-ku, Tokyo, Japan
| | - Masato S Ota
- Laboratory of Anatomy and Physiology, Department of Food and Nutrition, Japan Women's University, Bunkyo-ku, Tokyo, Japan.
| |
Collapse
|
30
|
Müthel S, Uyar B, He M, Krause A, Vitrinel B, Bulut S, Vasiljevic D, Marchal I, Kempa S, Akalin A, Tursun B. The conserved histone chaperone LIN-53 is required for normal lifespan and maintenance of muscle integrity in Caenorhabditis elegans. Aging Cell 2019; 18:e13012. [PMID: 31397537 PMCID: PMC6826145 DOI: 10.1111/acel.13012] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 06/27/2019] [Accepted: 07/02/2019] [Indexed: 12/27/2022] Open
Abstract
Whether extension of lifespan provides an extended time without health deteriorations is an important issue for human aging. However, to which degree lifespan and aspects of healthspan regulation might be linked is not well understood. Chromatin factors could be involved in linking both aging aspects, as epigenetic mechanisms bridge regulation of different biological processes. The epigenetic factor LIN‐53 (RBBP4/7) associates with different chromatin‐regulating complexes to safeguard cell identities in Caenorhabditis elegans as well as mammals, and has a role in preventing memory loss and premature aging in humans. We show that LIN‐53 interacts with the nucleosome remodeling and deacetylase (NuRD) complex in C. elegans muscles to ensure functional muscles during postembryonic development and in adults. While mutants for other NuRD members show a normal lifespan, animals lacking LIN‐53 die early because LIN‐53 depletion affects also the histone deacetylase complex Sin3, which is required for a normal lifespan. To determine why lin‐53 and sin‐3 mutants die early, we performed transcriptome and metabolomic analysis revealing that levels of the disaccharide trehalose are significantly decreased in both mutants. As trehalose is required for normal lifespan in C. elegans, lin‐53 and sin‐3 mutants could be rescued by either feeding with trehalose or increasing trehalose levels via the insulin/IGF1 signaling pathway. Overall, our findings suggest that LIN‐53 is required for maintaining lifespan and muscle integrity through discrete chromatin regulatory mechanisms. Since both LIN‐53 and its mammalian homologs safeguard cell identities, it is conceivable that its implication in lifespan regulation is also evolutionarily conserved.
Collapse
Affiliation(s)
- Stefanie Müthel
- Berlin Institute of Medical Systems Biology Berlin Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association Berlin Germany
| | - Bora Uyar
- Berlin Institute of Medical Systems Biology Berlin Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association Berlin Germany
| | - Mei He
- Berlin Institute of Medical Systems Biology Berlin Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association Berlin Germany
| | - Anne Krause
- Berlin Institute of Medical Systems Biology Berlin Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association Berlin Germany
| | - Burcu Vitrinel
- Berlin Institute of Medical Systems Biology Berlin Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association Berlin Germany
| | - Selman Bulut
- Berlin Institute of Medical Systems Biology Berlin Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association Berlin Germany
| | - Djordje Vasiljevic
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association Berlin Germany
| | - Iris Marchal
- Berlin Institute of Medical Systems Biology Berlin Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association Berlin Germany
| | - Stefan Kempa
- Berlin Institute of Medical Systems Biology Berlin Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association Berlin Germany
| | - Altuna Akalin
- Berlin Institute of Medical Systems Biology Berlin Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association Berlin Germany
| | - Baris Tursun
- Berlin Institute of Medical Systems Biology Berlin Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association Berlin Germany
| |
Collapse
|
31
|
de Diego I, Peleg S, Fuchs B. The role of lipids in aging-related metabolic changes. Chem Phys Lipids 2019; 222:59-69. [DOI: 10.1016/j.chemphyslip.2019.05.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 05/22/2019] [Accepted: 05/28/2019] [Indexed: 12/30/2022]
|
32
|
Metabolic Control of Stemness and Differentiation. Stem Cells Int 2019; 2019:6865956. [PMID: 31281382 PMCID: PMC6594243 DOI: 10.1155/2019/6865956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 05/22/2019] [Indexed: 11/18/2022] Open
|
33
|
Mohammad K, Dakik P, Medkour Y, Mitrofanova D, Titorenko VI. Quiescence Entry, Maintenance, and Exit in Adult Stem Cells. Int J Mol Sci 2019; 20:ijms20092158. [PMID: 31052375 PMCID: PMC6539837 DOI: 10.3390/ijms20092158] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/24/2019] [Accepted: 04/28/2019] [Indexed: 12/13/2022] Open
Abstract
Cells of unicellular and multicellular eukaryotes can respond to certain environmental cues by arresting the cell cycle and entering a reversible state of quiescence. Quiescent cells do not divide, but can re-enter the cell cycle and resume proliferation if exposed to some signals from the environment. Quiescent cells in mammals and humans include adult stem cells. These cells exhibit improved stress resistance and enhanced survival ability. In response to certain extrinsic signals, adult stem cells can self-renew by dividing asymmetrically. Such asymmetric divisions not only allow the maintenance of a population of quiescent cells, but also yield daughter progenitor cells. A multistep process of the controlled proliferation of these progenitor cells leads to the formation of one or more types of fully differentiated cells. An age-related decline in the ability of adult stem cells to balance quiescence maintenance and regulated proliferation has been implicated in many aging-associated diseases. In this review, we describe many traits shared by different types of quiescent adult stem cells. We discuss how these traits contribute to the quiescence, self-renewal, and proliferation of adult stem cells. We examine the cell-intrinsic mechanisms that allow establishing and sustaining the characteristic traits of adult stem cells, thereby regulating quiescence entry, maintenance, and exit.
Collapse
Affiliation(s)
- Karamat Mohammad
- Department of Biology, Concordia University, 7141 Sherbrooke Street, West, SP Building, Room 501-13, Montreal, QC H4B 1R6, Canada.
| | - Paméla Dakik
- Department of Biology, Concordia University, 7141 Sherbrooke Street, West, SP Building, Room 501-13, Montreal, QC H4B 1R6, Canada.
| | - Younes Medkour
- Department of Biology, Concordia University, 7141 Sherbrooke Street, West, SP Building, Room 501-13, Montreal, QC H4B 1R6, Canada.
| | - Darya Mitrofanova
- Department of Biology, Concordia University, 7141 Sherbrooke Street, West, SP Building, Room 501-13, Montreal, QC H4B 1R6, Canada.
| | - Vladimir I Titorenko
- Department of Biology, Concordia University, 7141 Sherbrooke Street, West, SP Building, Room 501-13, Montreal, QC H4B 1R6, Canada.
| |
Collapse
|
34
|
Delaney CE, Methot SP, Guidi M, Katic I, Gasser SM, Padeken J. Heterochromatic foci and transcriptional repression by an unstructured MET-2/SETDB1 co-factor LIN-65. J Cell Biol 2019; 218:820-838. [PMID: 30737265 PMCID: PMC6400574 DOI: 10.1083/jcb.201811038] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 01/22/2019] [Accepted: 01/25/2019] [Indexed: 12/14/2022] Open
Abstract
Delaney et al. show that the unstructured domain cofactor LIN-65 is essential for the stable formation of heterochromatic foci. It stably interacts with the H3K9 methyltransferase MET-2/SETDB1 and modulates MET-2 nuclear localization, activity, and H3K9me-mediated silencing in C. elegans. The segregation of the genome into accessible euchromatin and histone H3K9-methylated heterochromatin helps silence repetitive elements and tissue-specific genes. In Caenorhabditis elegans, MET-2, the homologue of mammalian SETDB1, catalyzes H3K9me1 and me2, yet like SETDB1, its regulation is enigmatic. Contrary to the cytosolic enrichment of overexpressed MET-2, we show that endogenous MET-2 is nuclear throughout development, forming perinuclear foci in a cell cycle–dependent manner. Mass spectrometry identified two cofactors that bind MET-2: LIN-65, a highly unstructured protein, and ARLE-14, a conserved GTPase effector. All three factors colocalize in heterochromatic foci. Ablation of lin-65, but not arle-14, mislocalizes and destabilizes MET-2, resulting in decreased H3K9 dimethylation, dispersion of heterochromatic foci, and derepression of MET-2 targets. Mutation of met-2 or lin-65 also disrupts the perinuclear anchoring of genomic heterochromatin. Loss of LIN-65, like that of MET-2, compromises temperature stress resistance and germline integrity, which are both linked to promiscuous repeat transcription and gene expression.
Collapse
Affiliation(s)
- Colin E Delaney
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Stephen P Methot
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Micol Guidi
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Iskra Katic
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Susan M Gasser
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland .,University of Basel, Faculty of Natural Sciences, Basel, Switzerland
| | - Jan Padeken
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| |
Collapse
|
35
|
Barbosa MC, Grosso RA, Fader CM. Hallmarks of Aging: An Autophagic Perspective. Front Endocrinol (Lausanne) 2019; 9:790. [PMID: 30687233 PMCID: PMC6333684 DOI: 10.3389/fendo.2018.00790] [Citation(s) in RCA: 155] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 12/17/2018] [Indexed: 12/16/2022] Open
Abstract
Autophagy is a major protein turnover pathway by which cellular components are delivered into the lysosomes for degradation and recycling. This intracellular process is able to maintain cellular homeostasis under stress conditions, and its dysregulation could lead to the development of physiological alterations. The autophagic activity has been found to decrease with age, likely contributing to the accumulation of damaged macromolecules and organelles during aging. Interestingly, failure of the autophagic process has been reported to worsen aging-associated diseases, such as neurodegeneration or cancer, among others. Likewise, it has been proposed in different organisms that maintenance of a proper autophagic activity contributes to extending longevity. In this review, we discuss recent papers showing the impact of autophagy on cell activity and age-associated diseases, highlighting the relevance of this process to the hallmarks of aging. Thus, understanding how autophagy plays an important role in aging opens new avenues for the discovery of biochemical and pharmacological targets and the development of novel anti-aging therapeutic approaches.
Collapse
Affiliation(s)
- María Carolina Barbosa
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología (IHEM), Universidad Nacional de Cuyo, CONICET, Mendoza, Argentina
| | - Rubén Adrián Grosso
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología (IHEM), Universidad Nacional de Cuyo, CONICET, Mendoza, Argentina
| | - Claudio Marcelo Fader
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología (IHEM), Universidad Nacional de Cuyo, CONICET, Mendoza, Argentina
- Facultad de Odontología, Universidad Nacional de Cuyo, Mendoza, Argentina
| |
Collapse
|
36
|
Mokalled MH, Poss KD. A Regeneration Toolkit. Dev Cell 2019; 47:267-280. [PMID: 30399333 DOI: 10.1016/j.devcel.2018.10.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 10/10/2018] [Accepted: 10/11/2018] [Indexed: 12/13/2022]
Abstract
The ability of animals to replace injured body parts has been a subject of fascination for centuries. The emerging importance of regenerative medicine has reinvigorated investigations of innate tissue regeneration, and the development of powerful genetic tools has fueled discoveries into how tissue regeneration occurs. Here, we present an overview of the armamentarium employed to probe regeneration in vertebrates, highlighting areas where further methodology advancement will deepen mechanistic findings.
Collapse
Affiliation(s)
- Mayssa H Mokalled
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Kenneth D Poss
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA; Regeneration Next, Duke University, Durham, NC 27710, USA.
| |
Collapse
|
37
|
Skirbekk VF, Staudinger UM, Cohen JE. How to Measure Population Aging? The Answer Is Less than Obvious: A Review. Gerontology 2018; 65:136-144. [PMID: 30544101 DOI: 10.1159/000494025] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 09/25/2018] [Indexed: 11/19/2022] Open
Abstract
Usually, population aging is measured to inform fiscal and social planning because it is considered to indicate the burden that an elderly population presents to the economic, social security, and health systems of a society. Measures of population aging are expected to indicate shifts in the distribution of individuals' attributes (e.g., chronological age, health) within a population that are relevant to assessing the burden. We claim that chronological age - even though it is the attribute most broadly used - may frequently not be the best measure to satisfy this purpose. A distribution of chronological age per se does not present a burden. Rather, burdens arise from the characteristics that supposedly or actually accompany chronological ages. We posit that in addition to chronological age, meaningful measures of population aging should reflect, for instance, the distribution of economic productivity, health, functional capacities, or biological age, as these attributes may more directly assess the burden on the socioeconomic and health systems. Here, we illustrate some limitations of measures of population aging based on each kind of measure, including chronological age, and review alternative measures that may better inform fiscal, social, and health planning.
Collapse
Affiliation(s)
- Vegard F Skirbekk
- Robert N. Butler Columbia Aging Center, Columbia University, New York, New York, USA, .,Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway,
| | - Ursula M Staudinger
- Robert N. Butler Columbia Aging Center, Columbia University, New York, New York, USA.,Department of Sociomedical Science, Mailman School of Public Health, Columbia University, New York, New York, USA
| | - Joel E Cohen
- Rockefeller University, New York, New York, USA.,Earth Institute and Department of Statistics, Columbia University, New York, New York, USA.,Department of Statistics, University of Chicago, Chicago, Illinois, USA
| |
Collapse
|
38
|
Dual roles of mitochondrial fusion gene FZO1 in yeast age asymmetry and in longevity mediated by a novel ATG32-dependent retrograde response. Biogerontology 2018; 20:93-107. [PMID: 30298458 DOI: 10.1007/s10522-018-9779-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 10/04/2018] [Indexed: 12/27/2022]
Abstract
The replicative lifespan of the yeast Saccharomyces cerevisiae models the aging of stem cells. Age asymmetry between the mother and daughter cells is established during each cell division, such that the daughter retains the capacity for self-renewal while this ability is diminished in the mother. The segregation of fully-functional mitochondria to daughter cells is one mechanism that underlies this age asymmetry. In this study, we have examined the role of mitochondrial dynamics in this phenomenon. Mitochondrial dynamics involve the processes of fission and fusion. Out of the three fusion and three fission genes tested, we have found that only FZO1 is required for the segregation of fully-functional mitochondria to daughter cells and in the maintenance of age asymmetry as manifested in the potential of daughters for a full replicative lifespan despite its deterioration in their mothers. The quality of mitochondria is determined by their turnover, and we have also discovered that deletion of FZO1 reduces mitophagy. Mitochondrial dysfunction elicits a compensatory retrograde response that extends replicative lifespan. Typically, the dysfunction that triggers this response encompasses energy production. The disruption of mitochondrial dynamics by deletion of FZO1 also activates the retrograde response to extend replicative lifespan. We call this novel pathway the mitochondrial dynamics-associated retrograde response (MDARR) because it is distinct in the signal proximal to the mitochondrion that initiates it. Furthermore, the MDARR engages the mitophagy receptor Atg32 on the mitochondrial surface, and we propose that this is due to the accumulation of Atg32-Atg11-Dnm1 complexes on the mitochondrion in the absence of Fzo1 activity. MDARR can be masked by the operation of the 'classic' retrograde response.
Collapse
|
39
|
Doxtader KA, Wang P, Scarborough AM, Seo D, Conrad NK, Nam Y. Structural Basis for Regulation of METTL16, an S-Adenosylmethionine Homeostasis Factor. Mol Cell 2018; 71:1001-1011.e4. [PMID: 30197297 PMCID: PMC6367934 DOI: 10.1016/j.molcel.2018.07.025] [Citation(s) in RCA: 125] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 06/25/2018] [Accepted: 07/20/2018] [Indexed: 12/12/2022]
Abstract
S-adenosylmethionine (SAM) is an essential metabolite that acts as a cofactor for most methylation events in the cell. The N6-methyladenosine (m6A) methyltransferase METTL16 controls SAM homeostasis by regulating the abundance of SAM synthetase MAT2A mRNA in response to changing intracellular SAM levels. Here we present crystal structures of METTL16 in complex with MAT2A RNA hairpins to uncover critical molecular mechanisms underlying the regulated activity of METTL16. The METTL16-RNA complex structures reveal atomic details of RNA substrates that drive productive methylation by METTL16. In addition, we identify a polypeptide loop in METTL16 near the SAM binding site with an autoregulatory role. We show that mutations that enhance or repress METTL16 activity in vitro correlate with changes in MAT2A mRNA levels in cells. Thus, we demonstrate the structural basis for the specific activity of METTL16 and further suggest the molecular mechanisms by which METTL16 efficiency is tuned to regulate SAM homeostasis.
Collapse
Affiliation(s)
- Katelyn A Doxtader
- Cecil H. and Ida Green Center for Reproductive Biology Sciences and Division of Basic Reproductive Biology Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ping Wang
- Cecil H. and Ida Green Center for Reproductive Biology Sciences and Division of Basic Reproductive Biology Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Anna M Scarborough
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Dahee Seo
- Cecil H. and Ida Green Center for Reproductive Biology Sciences and Division of Basic Reproductive Biology Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Nicholas K Conrad
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yunsun Nam
- Cecil H. and Ida Green Center for Reproductive Biology Sciences and Division of Basic Reproductive Biology Research, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| |
Collapse
|
40
|
Theodorou K, Boon RA. Endothelial Cell Metabolism in Atherosclerosis. Front Cell Dev Biol 2018; 6:82. [PMID: 30131957 PMCID: PMC6090045 DOI: 10.3389/fcell.2018.00082] [Citation(s) in RCA: 107] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 07/13/2018] [Indexed: 12/13/2022] Open
Abstract
Atherosclerosis and its sequelae, such as myocardial infarction and stroke, are the leading cause of death worldwide. Vascular endothelial cells (EC) play a critical role in vascular homeostasis and disease. Atherosclerosis as well as its independent risk factors including diabetes, obesity, and aging, are hallmarked by endothelial activation and dysfunction. Metabolic pathways have emerged as key regulators of many EC functions, including angiogenesis, inflammation, and barrier function, processes which are deregulated during atherogenesis. In this review, we highlight the role of glucose, fatty acid, and amino acid metabolism in EC functions during physiological and pathological states, specifically atherosclerosis, diabetes, obesity and aging.
Collapse
Affiliation(s)
- Kosta Theodorou
- Centre of Molecular Medicine, Institute of Cardiovascular Regeneration, Goethe-University, Frankfurt am Main, Germany
| | - Reinier A Boon
- Centre of Molecular Medicine, Institute of Cardiovascular Regeneration, Goethe-University, Frankfurt am Main, Germany.,German Center for Cardiovascular Research DZHK, Partner Site Rhine-Main, Berlin, Germany.,Department of Physiology, Amsterdam Cardiovascular Sciences, VU University Medical Center, Amsterdam, Netherlands
| |
Collapse
|
41
|
Estimation of the cancer risk induced by therapies targeting stem cell replication and treatment recommendations. Sci Rep 2018; 8:11776. [PMID: 30082874 PMCID: PMC6078959 DOI: 10.1038/s41598-018-29967-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 07/17/2018] [Indexed: 11/09/2022] Open
Abstract
Rejuvenation of stem cell activity might increase life expectancy by prolonging functionality of organs. Higher stem cell replication rates also bear the risk of cancer. The extent of this risk is not known. While it is difficult to evaluate this cancer risk in experiments, it can be estimated using a mathematical model for tissue homeostasis by stem cell replication and associated cancer risk. The model recapitulates the observation that treatments targeting stem cell replication can induce a substantial delay of organ failure. The model predicts that the cancer risk is minor under particular conditions. It depends on the assumed implications for cell damage repair during treatment. The benefit of rejuvenation therapy and its impact on cancer risk depend on the biological age at the time of treatment and on the overall cell turnover rate of the organs. Different organs have to be considered separately in the planning of systemic treatments. In recent years, the transfer of blood from young to old individuals was shown to bear the potential of rejuvenation of stem cell activity. In this context, the model predicts that the treatment schedule is critical for success and that schedules successful in animal experiments are not transferable to humans. Guidelines for successful protocols are proposed. The model presented here may be used as a guidance for the development of stem cell rejuvenation treatment protocols and the identification of critical parameters for cancer risk.
Collapse
|
42
|
Chaker D, Mouawad C, Azar A, Quilliot D, Achkar I, Fajloun Z, Makdissy N. Inhibition of the RhoGTPase Cdc42 by ML141 enhances hepatocyte differentiation from human adipose-derived mesenchymal stem cells via the Wnt5a/PI3K/miR-122 pathway: impact of the age of the donor. Stem Cell Res Ther 2018; 9:167. [PMID: 29921325 PMCID: PMC6009972 DOI: 10.1186/s13287-018-0910-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 05/08/2018] [Accepted: 05/20/2018] [Indexed: 12/11/2022] Open
Abstract
Background Human adipose-derived mesenchymal stem cells (hADSCs) are promising cells that may promote hepatocyte differentiation (Hep-Dif) and improve liver function, but the involvement of Cdc42, a key small RhoGTPase which plays a crucial role in aging, is still not well established. We hypothesized that the inhibition of Cdc42 may rescue the hepatogenic potential of hADSCs derived from aged donors. Methods hADSCs isolated from 61 women of different ages were cultured for evaluation of the proliferation of cells, adherence, apoptosis, immunomodulation, immunophenotyping, multipotency, gene expression, and cell function during Hep-Dif. Inhibition of Cdc42 by ML141 was realized during two phases: initiation (days –2 to 14 (D–2/14)) from undifferentiated to hepatoblast-like cells, or maturation (days 14 to 28 (D14/28)) from undifferentiated to hepatocyte-like cells. Mechanistic insights of the Wnt(s)/MAPK/PI3K/miR-122 pathways were studied. Results Cdc42 activity in undifferentiated hADSCs showed an age-dependent significant increase in Cdc42-GTP correlated to a decrease in Cdc42GAP; the low potentials of cell proliferation, doubling, adherence, and immunomodulatory ability (proinflammatory over anti-inflammatory) contrary to the apoptotic index of the aged group were significantly reversed by ML141. Aged donor cells showed a decreased potential for Hep-Dif which was rescued by ML141 treatment, giving rise to mature and functional hepatocyte-like cells as assessed by hepatic gene expression, cytochrome activity, urea and albumin production, low-density lipoprotein (LDL) uptake, and glycogen storage. ML141-induced Hep-Dif showed an improvement in mesenchymal-epithelial transition, a switch from Wtn-3a/β-catenin to Wnt5a signaling, involvement of PI3K/PKB but not the MAPK (ERK/JNK/p38) pathway, induction of miR-122 expression, reinforcing the exosomes release and the production of albumin, and epigenetic changes. Inhibition of PI3K and miR-122 abolished completely the effects of ML141 indicating that inhibition of Cdc42 promotes the Hep-Dif through a Wnt5a/PI3K/miR-122/HNF4α/albumin/E-cadherin-positive action. The ML141(D–2/14) protocol had more pronounced effects when compared with ML141(D14/28); inhibition of DNA methylation in combination with ML141(D–2/14) showed more efficacy in rescuing the Hep-Dif of aged hADSCs. In addition to Hep-Dif, the multipotency of aged hADSC-treated ML141 was observed by rescuing the adipocyte and neural differentiation by inducing PPARγ/FABP4 and NeuN/O4 but inhibiting Pref-1 and GFAP, respectively. Conclusion ML141 has the potential to reverse the age-related aberrations in aged stem cells and promotes their hepatogenic differentiation. Selective inhibition of Cdc42 could be a potential target of drug therapy for aging and may give new insights on the improvement of Hep-Dif. Electronic supplementary material The online version of this article (10.1186/s13287-018-0910-5) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Diana Chaker
- Lebanese University, Doctoral School for Sciences and Technology, Laboratory of Applied Biotechnology, Azm Center for Research in Biotechnology and its Applications, Tripoli, Lebanon.,Reviva Regenerative Medicine Center, Human Genetic Center, Middle East Institute of Health Hospital, Bsalim, Lebanon.,Paris Saclay University, Doctoral School, Therapeutical Innovation, Inserm UMR935, Villejuif, France
| | | | - Albert Azar
- Reviva Regenerative Medicine Center, Human Genetic Center, Middle East Institute of Health Hospital, Bsalim, Lebanon
| | - Didier Quilliot
- Diabetologia-Endocrinology & Nutrition, CHRU Nancy, INSERM 954, University Henri Poincaré de Lorraine, Faculty of Medicine, Nancy, France
| | | | - Ziad Fajloun
- Lebanese University, Doctoral School for Sciences and Technology, Laboratory of Applied Biotechnology, Azm Center for Research in Biotechnology and its Applications, Tripoli, Lebanon.,Lebanese University, Faculty of Sciences III, Department of Biology, Kobbe, Lebanon
| | - Nehman Makdissy
- Lebanese University, Doctoral School for Sciences and Technology, Laboratory of Applied Biotechnology, Azm Center for Research in Biotechnology and its Applications, Tripoli, Lebanon. .,Lebanese University, Faculty of Sciences III, Department of Biology, Kobbe, Lebanon.
| |
Collapse
|
43
|
Accelerated aging in schizophrenia and related disorders: Future research. Schizophr Res 2018; 196:4-8. [PMID: 28689755 DOI: 10.1016/j.schres.2017.06.034] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 06/15/2017] [Accepted: 06/19/2017] [Indexed: 01/17/2023]
Abstract
Several lines of evidence suggest schizophrenia is a segmental progeria, that is, some but not all aspects of accelerated aging may be present. However, the evidence has not been consistent. Problems with matching and confounding may account for some of these discrepancies. Given the etiopathophysiological heterogeneity of schizophrenia, it is possible that only a specific pathophysiological group within schizophrenia is associated with progeroid features, while others are not, or that one group is associated with a particular segment of aging features, while other progeroid features are found in another pathophysiological subgroup. In the aging research field, significant progress has been made in identifying the molecular pathways that confer aging: epigenetic changes, inflammation, proteostasis, adult stem cell function, metabolic changes, and adaptation to stress, and macromolecular damage. In addition to replication and clarification of existing kinds of evidence, examining these aging pathways would improve our understanding of progeria in schizophrenia.
Collapse
|
44
|
Abstract
Epigenetic deregulation, such as the reduction of histone acetylation levels, is thought to be causally linked to various maladies associated with aging. Consequently, histone deacetylase inhibitors are suggested to serve as epigenetic therapy by increasing histone acetylation. However, previous work suggests that many non-histone proteins, including metabolic enzymes, are also acetylated and that post transitional modifications may impact their activity. Furthermore, deacetylase inhibitors were recently shown to impact the acetylation of a variety of proteins. By utilizing a novel technique to measure oxygen consumption rate from whole living tissue, we demonstrate that treatment of whole living fly heads by the HDAC/KDAC inhibitors sodium butyrate and Trichostatin A, induces a rapid and transient increase of oxygen consumption rate. In addition, our study indicates that the rate increase is markedly attenuated in midlife fly head tissue. Overall, our data suggest that HDAC/KDAC inhibitors may induce enhanced mitochondrial activity in a rapid manner. This observed metabolic boost provides further, but novel evidence, that treating various maladies with deacetylase inhibitors may be beneficial.
Collapse
|
45
|
Gontier G, Iyer M, Shea JM, Bieri G, Wheatley EG, Ramalho-Santos M, Villeda SA. Tet2 Rescues Age-Related Regenerative Decline and Enhances Cognitive Function in the Adult Mouse Brain. Cell Rep 2018; 22:1974-1981. [PMID: 29466726 PMCID: PMC5870899 DOI: 10.1016/j.celrep.2018.02.001] [Citation(s) in RCA: 118] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 11/20/2017] [Accepted: 01/31/2018] [Indexed: 12/21/2022] Open
Abstract
Restoring adult stem cell function provides an exciting approach for rejuvenating the aging brain. However, molecular mechanisms mediating neurogenic rejuvenation remain elusive. Here we report that the enzyme ten eleven translocation methylcytosine dioxygenase 2 (Tet2), which catalyzes the production of 5-hydroxymethylcytosine (5hmC), rescues age-related decline in adult neurogenesis and enhances cognition in mice. We detected a decrease in Tet2 expression and 5hmC levels in the aged hippocampus associated with adult neurogenesis. Mimicking an aged condition in young adults by abrogating Tet2 expression within the hippocampal neurogenic niche, or adult neural stem cells, decreased neurogenesis and impaired learning and memory. In a heterochronic parabiosis rejuvenation model, hippocampal Tet2 expression was restored. Overexpressing Tet2 in the hippocampal neurogenic niche of mature adults increased 5hmC associated with neurogenic processes, offset the precipitous age-related decline in neurogenesis, and enhanced learning and memory. Our data identify Tet2 as a key molecular mediator of neurogenic rejuvenation.
Collapse
Affiliation(s)
- Geraldine Gontier
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Manasi Iyer
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Jeremy M Shea
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Gregor Bieri
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Elizabeth G Wheatley
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA; Developmental and Stem Cell Biology Graduate Program, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Miguel Ramalho-Santos
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Saul A Villeda
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA; Developmental and Stem Cell Biology Graduate Program, University of California, San Francisco, San Francisco, CA 94143, USA; Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, San Francisco, CA 94143, USA; The Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94143, USA.
| |
Collapse
|
46
|
Pustovalova M, Astrelina ТA, Grekhova A, Vorobyeva N, Tsvetkova A, Blokhina T, Nikitina V, Suchkova Y, Usupzhanova D, Brunchukov V, Kobzeva I, Karaseva Т, Ozerov IV, Samoylov A, Bushmanov A, Leonov S, Izumchenko E, Zhavoronkov A, Klokov D, Osipov AN. Residual γH2AX foci induced by low dose x-ray radiation in bone marrow mesenchymal stem cells do not cause accelerated senescence in the progeny of irradiated cells. Aging (Albany NY) 2018; 9:2397-2410. [PMID: 29165316 PMCID: PMC5723693 DOI: 10.18632/aging.101327] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 11/11/2017] [Indexed: 01/09/2023]
Abstract
Mechanisms underlying the effects of low-dose ionizing radiation (IR) exposure (10-100 mGy) remain unknown. Here we present a comparative study of early (less than 24h) and delayed (up to 11 post-irradiation passages) radiation effects caused by low (80 mGy) vs intermediate (1000 mGy) dose X-ray exposure in cultured human bone marrow mesenchymal stem cells (MSCs). We show that γН2АХ foci induced by an intermediate dose returned back to the control value by 24 h post-irradiation. In contrast, low-dose irradiation resulted in residual γН2АХ foci still present at 24 h. Notably, these low dose induced residual γН2АХ foci were not co-localized with рАТМ foci and were observed predominantly in the proliferating Кi67 positive (Кi67+) cells. The number of γН2АХ foci and the fraction of nonproliferating (Кi67-) and senescent (SA-β-gal+) cells measured at passage 11 were increased in cultures exposed to an intermediate dose compared to unirradiated controls. These delayed effects were not seen in the progeny of cells that were irradiated with low-dose X-rays, although such exposure resulted in residual γН2АХ foci in directly irradiated cells. Taken together, our results support the hypothesis that the low-dose IR induced residual γH2AХ foci do not play a role in delayed irradiation consequences, associated with cellular senescence in cultured MSCs.
Collapse
Affiliation(s)
- Margarita Pustovalova
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia.,Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow 119991, Russia
| | - Тatiana A Astrelina
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia
| | - Anna Grekhova
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia.,Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow 119991, Russia.,Emanuel Institute for Biochemical Physics, Russian Academy of Sciences, Moscow 119991, Russia
| | - Natalia Vorobyeva
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia.,Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow 119991, Russia
| | - Anastasia Tsvetkova
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia.,Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russia
| | - Taisia Blokhina
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia.,Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow 119991, Russia
| | - Victoria Nikitina
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia
| | - Yulia Suchkova
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia
| | - Daria Usupzhanova
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia
| | - Vitalyi Brunchukov
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia
| | - Irina Kobzeva
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia
| | - Тatiana Karaseva
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia
| | - Ivan V Ozerov
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia.,Insilico Medicine, Inc, ETC, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Aleksandr Samoylov
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia
| | - Andrey Bushmanov
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia
| | - Sergey Leonov
- Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russia.,Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia
| | - Evgeny Izumchenko
- Department of Otolaryngology-Head and Neck Cancer Research, Johns Hopkins University, School of Medicine, Baltimore, MD 21218, USA
| | - Alex Zhavoronkov
- Insilico Medicine, Inc, ETC, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Dmitry Klokov
- Canadian Nuclear Laboratories, Chalk River, Ontario K0J1P0, Canada.,University of Ottawa, Ottawa, Ontario K1N6N5, Canada
| | - Andreyan N Osipov
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow 123098, Russia.,Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow 119991, Russia.,Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russia.,Insilico Medicine, Inc, ETC, Johns Hopkins University, Baltimore, MD 21218, USA
| |
Collapse
|
47
|
Abstract
Metabolic changes are hallmarks of aging and genetic and pharmacologic alterations of relevant pathways can extend life span. In this review, we will outline how cellular biochemistry and energy homeostasis change during aging. We will highlight protein quality control, mitochondria, epigenetics, nutrient-sensing pathways, as well as the interplay between these systems with respect to their impact on cellular health.
Collapse
Affiliation(s)
- Andre Catic
- Huffington Center on Aging, Stem Cells and Regenerative Medicine Center, Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, United States.
| |
Collapse
|
48
|
O'Callaghan C, Vassilopoulos A. Sirtuins at the crossroads of stemness, aging, and cancer. Aging Cell 2017; 16:1208-1218. [PMID: 28994177 PMCID: PMC5676072 DOI: 10.1111/acel.12685] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2017] [Indexed: 12/27/2022] Open
Abstract
Sirtuins are stress‐responsive proteins that direct various post‐translational modifications (PTMs) and as a result, are considered to be master regulators of several cellular processes. They are known to both extend lifespan and regulate spontaneous tumor development. As both aging and cancer are associated with altered stem cell function, the possibility that the involvement of sirtuins in these events is mediated by their roles in stem cells is worthy of investigation. Research to date suggests that the individual sirtuin family members can differentially regulate embryonic, hematopoietic as well as other adult stem cells in a tissue‐ and cell type‐specific context. Sirtuin‐driven regulation of both cell differentiation and signaling pathways previously involved in stem cell maintenance has been described where downstream effectors involved determine the biological outcome. Similarly, diverse roles have been reported in cancer stem cells (CSCs), depending on the tissue of origin. This review highlights the current knowledge which places sirtuins at the intersection of stem cells, aging, and cancer. By outlining the plethora of stem cell‐related roles for individual sirtuins in various contexts, our purpose was to provide an indication of their significance in relation to cancer and aging, as well as to generate a clearer picture of their therapeutic potential. Finally, we propose future directions which will contribute to the better understanding of sirtuins, thereby further unraveling the full repertoire of sirtuin functions in both normal stem cells and CSCs.
Collapse
Affiliation(s)
- Carol O'Callaghan
- Laboratory for Molecular Cancer Biology Department of Radiation Oncology Feinberg School of Medicine Northwestern University Chicago IL USA
| | - Athanassios Vassilopoulos
- Laboratory for Molecular Cancer Biology Department of Radiation Oncology Feinberg School of Medicine Northwestern University Chicago IL USA
- Robert H. Lurie Comprehensive Cancer Center Northwestern University Chicago IL USA
| |
Collapse
|
49
|
Abstract
The meeting covered a plethora of rapidly evolving approaches and areas, such as organoid cultures modeling tissues and organs; stem cell-specific metabolites revealing new signaling pathways; single-cell technologies discovering new cell types and exploring stem cell niche interactions; novel methods studying stem cells in aging and cancer; lineage-tracing experiments exploring cell plasticity of tissues before and after injury; epigenetic studies illuminating cell reprogramming; new protocols improving cells for regenerative purposes; and several other timely and exciting topics.
Collapse
Affiliation(s)
- Thomas Graf
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology and Universitat Pompeu Fabra, Barcelona, Spain.
| |
Collapse
|
50
|
|