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He M, Borlak J. A genomic perspective of the aging human and mouse lung with a focus on immune response and cellular senescence. Immun Ageing 2023; 20:58. [PMID: 37932771 PMCID: PMC10626779 DOI: 10.1186/s12979-023-00373-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 09/12/2023] [Indexed: 11/08/2023]
Abstract
BACKGROUND The aging lung is a complex process and influenced by various stressors, especially airborne pathogens and xenobiotics. Additionally, a lifetime exposure to antigens results in structural and functional changes of the lung; yet an understanding of the cell type specific responses remains elusive. To gain insight into age-related changes in lung function and inflammaging, we evaluated 89 mouse and 414 individual human lung genomic data sets with a focus on genes mechanistically linked to extracellular matrix (ECM), cellular senescence, immune response and pulmonary surfactant, and we interrogated single cell RNAseq data to fingerprint cell type specific changes. RESULTS We identified 117 and 68 mouse and human genes linked to ECM remodeling which accounted for 46% and 27%, respectively of all ECM coding genes. Furthermore, we identified 73 and 31 mouse and human genes linked to cellular senescence, and the majority code for the senescence associated secretory phenotype. These cytokines, chemokines and growth factors are primarily secreted by macrophages and fibroblasts. Single-cell RNAseq data confirmed age-related induced expression of marker genes of macrophages, neutrophil, eosinophil, dendritic, NK-, CD4+, CD8+-T and B cells in the lung of aged mice. This included the highly significant regulation of 20 genes coding for the CD3-T-cell receptor complex. Conversely, for the human lung we primarily observed macrophage and CD4+ and CD8+ marker genes as changed with age. Additionally, we noted an age-related induced expression of marker genes for mouse basal, ciliated, club and goblet cells, while for the human lung, fibroblasts and myofibroblasts marker genes increased with age. Therefore, we infer a change in cellular activity of these cell types with age. Furthermore, we identified predominantly repressed expression of surfactant coding genes, especially the surfactant transporter Abca3, thus highlighting remodeling of surfactant lipids with implications for the production of inflammatory lipids and immune response. CONCLUSION We report the genomic landscape of the aging lung and provide a rationale for its growing stiffness and age-related inflammation. By comparing the mouse and human pulmonary genome, we identified important differences between the two species and highlight the complex interplay of inflammaging, senescence and the link to ECM remodeling in healthy but aged individuals.
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Affiliation(s)
- Meng He
- Centre for Pharmacology and Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Jürgen Borlak
- Centre for Pharmacology and Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
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Otsuka K, Iwasaki T. Insights into radiation carcinogenesis based on dose-rate effects in tissue stem cells. Int J Radiat Biol 2023; 99:1503-1521. [PMID: 36971595 DOI: 10.1080/09553002.2023.2194398] [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: 05/05/2022] [Accepted: 03/16/2023] [Indexed: 03/29/2023]
Abstract
PURPOSE Increasing epidemiological and biological evidence suggests that radiation exposure enhances cancer risk in a dose-dependent manner. This can be attributed to the 'dose-rate effect,' where the biological effect of low dose-rate radiation is lower than that of the same dose at a high dose-rate. This effect has been reported in epidemiological studies and experimental biology, although the underlying biological mechanisms are not completely understood. In this review, we aim to propose a suitable model for radiation carcinogenesis based on the dose-rate effect in tissue stem cells. METHODS We surveyed and summarized the latest studies on the mechanisms of carcinogenesis. Next, we summarized the radiosensitivity of intestinal stem cells and the role of dose-rate in the modulation of stem-cell dynamics after irradiation. RESULTS Consistently, driver mutations can be detected in most cancers from past to present, supporting the hypothesis that cancer progression is initiated by the accumulation of driver mutations. Recent reports demonstrated that driver mutations can be observed even in normal tissues, which suggests that the accumulation of mutations is a necessary condition for cancer progression. In addition, driver mutations in tissue stem cells can cause tumors, whereas they are not sufficient when they occur in non-stem cells. For non-stem cells, tissue remodeling induced by marked inflammation after the loss of tissue cells is important in addition to the accumulation of mutations. Therefore, the mechanism of carcinogenesis differs according to the cell type and magnitude of stress. In addition, our results indicated that non-irradiated stem cells tend to be eliminated from three-dimensional cultures of intestinal stem cells (organoids) composed of irradiated and non-irradiated stem cells, supporting the stem-cell competition. CONCLUSIONS We propose a unique scheme in which the dose-rate dependent response of intestinal stem cells incorporates the concept of the threshold of stem-cell competition and context-dependent target shift from stem cells to whole tissue. The concept highlights four key issues that should be considered in radiation carcinogenesis: i.e. accumulation of mutations; tissue reconstitution; stem-cell competition; and environmental factors like epigenetic modifications.
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Affiliation(s)
- Kensuke Otsuka
- Biology and Environmental Chemistry Division, Sustainable System Research Laboratory, Central Research Institute of Electric Power Industry, Tokyo, Japan
| | - Toshiyasu Iwasaki
- Strategy and Planning Division, Sustainable System Research Laboratory, Central Research Institute of Electric Power Industry, Tokyo, Japan
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3
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Chico-Sordo L, Polonio AM, Córdova-Oriz I, Medrano M, Herraiz S, Bronet F, García-Velasco JA, Varela E. Telomeres and oocyte maturation rate are not reduced by COVID-19 except in severe cases. Reproduction 2022; 164:259-267. [PMID: 36136831 DOI: 10.1530/rep-22-0243] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 09/22/2022] [Indexed: 11/08/2022]
Abstract
In brief COVID-19 does not affect the telomeres or fertility outcomes in mild cases. However, in women with severe symptoms, telomeres of granulosa cells are shorter, and the oocyte maturation rate is decreased. Abstract The coronavirus SARS-CoV-2 causes COVID-19 disease and affects primarily the lungs and also other organs, causing accelerated cell aging. One of the main pathways involved in aging is telomere attrition, which ultimately leads to defective tissue regeneration and organ dysfunction. Indeed, short telomeres in aged people aggravate the COVID-19 symptoms, and COVID-19 survivors showed shorter telomeres in blood cells. The SARS-CoV-2 has been detected in testis, but the ovaries, which express the viral entry factors, have not been fully explored. Our objective was to analyze telomeres and reproductive outcomes in women who had COVID-19 and controls. In this prospective cohort study, granulosa cells (GCs) and blood were collected from 65 women. Telomere length (TL) was measured by high-throughput in situ hybridization. Mean TL of GCs and peripheral blood mononuclear cells (PBMCs) was alike in control and mild cases. However, mean TL of GCs was lower in severe cases compared to controls (P = 0.017). Control and COVID groups had similar ovarian reserve and number of total oocytes after puncture. However, the oocyte maturation rate was lower in severe cases (P = 0.018). Interestingly, a positive correlation between the oocyte maturation rate and TL of GCs was found in the control group (P = 0.024). Our findings point to a potential impact of the coronavirus infection on telomeres and reproductive outcomes in severe cases. This might be considered upon possible new SARS-CoV threats, to favor treatments that enhance oocyte maturation in women severely affected by coronavirus undergoing ART.
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Affiliation(s)
- L Chico-Sordo
- IVI Foundation, The Health Research Institute La Fe (IIS La Fe) - Edificio Biopolo, Valencia, Spain
| | - A M Polonio
- IVI Foundation, The Health Research Institute La Fe (IIS La Fe) - Edificio Biopolo, Valencia, Spain
| | - I Córdova-Oriz
- IVI Foundation, The Health Research Institute La Fe (IIS La Fe) - Edificio Biopolo, Valencia, Spain
| | - M Medrano
- IVI Foundation, The Health Research Institute La Fe (IIS La Fe) - Edificio Biopolo, Valencia, Spain
| | - S Herraiz
- IVI Foundation, The Health Research Institute La Fe (IIS La Fe) - Edificio Biopolo, Valencia, Spain
| | | | - J A García-Velasco
- IVI Foundation, The Health Research Institute La Fe (IIS La Fe) - Edificio Biopolo, Valencia, Spain.,IVIRMA Madrid, Madrid, Spain.,Rey Juan Carlos University, Edificio Departamental II, Alcorcón, Madrid, Spain
| | - E Varela
- IVI Foundation, The Health Research Institute La Fe (IIS La Fe) - Edificio Biopolo, Valencia, Spain.,Rey Juan Carlos University, Edificio Departamental II, Alcorcón, Madrid, Spain
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4
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Lee HJ, Lee WJ, Hwang SC, Choe Y, Kim S, Bok E, Lee S, Kim SJ, Kim HO, Ock SA, Noh HS, Rho GJ, Lee SI, Lee SL. Chronic inflammation-induced senescence impairs immunomodulatory properties of synovial fluid mesenchymal stem cells in rheumatoid arthritis. Stem Cell Res Ther 2021; 12:502. [PMID: 34521481 PMCID: PMC8439066 DOI: 10.1186/s13287-021-02453-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 06/11/2021] [Indexed: 12/29/2022] Open
Abstract
Background Although the immunomodulatory properties of mesenchymal stem cells (MSCs) have been highlighted as a new therapy for autoimmune diseases, including rheumatoid arthritis (RA), the disease-specific characteristics of MSCs derived from elderly RA patients are not well understood. Methods We established MSCs derived from synovial fluid (SF) from age-matched early (average duration of the disease: 1.7 years) and long-standing (average duration of the disease: 13.8 years) RA patients (E-/L-SF-MSCs) and then analyzed the MSC characteristics such as stemness, proliferation, cellular senescence, in vitro differentiation, and in vivo immunomodulatory properties. Results The presence of MSC populations in the SF from RA patients was identified. We found that L-SF-MSCs exhibited impaired proliferation, intensified cellular senescence, reduced immunomodulatory properties, and attenuated anti-arthritic capacity in an RA animal model. In particular, E-SF-MSCs demonstrated cellular senescence progression and attenuated immunomodulatory properties similar to those of L-SF-MSC in an RA joint-mimetic milieu due to hypoxia and pro-inflammatory cytokine exposure. Due to a long-term exposure to the chronic inflammatory milieu, cellular senescence, attenuated immunomodulatory properties, and the loss of anti-arthritic potentials were more often identified in SF-MSCs in a long-term RA than early RA. Conclusion We conclude that a chronic RA inflammatory milieu affects the MSC potential. Therefore, this work addresses the importance of understanding MSC characteristics during disease states prior to their application in patients. Graphical abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13287-021-02453-z.
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Affiliation(s)
- Hyeon-Jeong Lee
- College of Veterinary Medicine, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Won-Jae Lee
- College of Veterinary Medicine, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Sun-Chul Hwang
- Department of Orthopaedic Surgery, Gyeongsang National University School of Medicine and Hospital, Jinju, 52727, Republic of Korea
| | - Yongho Choe
- College of Veterinary Medicine, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Saetbyul Kim
- College of Veterinary Medicine, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Eunyeong Bok
- College of Veterinary Medicine, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Sangyeob Lee
- College of Veterinary Medicine, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Seung-Joon Kim
- College of Veterinary Medicine, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Hyun-Ok Kim
- Department of Internal Medicine and Institute of Health Sciences, Gyeongsang National University School of Medicine and Hospital, Jinju, 52727, Republic of Korea
| | - Sun-A Ock
- Animal Biotechnology Division, National Institute of Animal Science, Rural Development Administration, 1500 Kongjwipatjwi-ro, Isero-myeon, Wanju-gun, Jeollabuk-do, 565-851, Republic of Korea
| | - Hae-Sook Noh
- Department of Internal Medicine and Institute of Health Sciences, Gyeongsang National University School of Medicine and Hospital, Jinju, 52727, Republic of Korea
| | - Gyu-Jin Rho
- College of Veterinary Medicine, Gyeongsang National University, Jinju, 52828, Republic of Korea.,Research Institute of Life Sciences, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Sang-Il Lee
- Department of Internal Medicine and Institute of Health Sciences, Gyeongsang National University School of Medicine and Hospital, Jinju, 52727, Republic of Korea.
| | - Sung-Lim Lee
- College of Veterinary Medicine, Gyeongsang National University, Jinju, 52828, Republic of Korea. .,Research Institute of Life Sciences, Gyeongsang National University, Jinju, 52828, Republic of Korea.
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5
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Telomeres: New players in immune-mediated inflammatory diseases? J Autoimmun 2021; 123:102699. [PMID: 34265700 DOI: 10.1016/j.jaut.2021.102699] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 07/02/2021] [Accepted: 07/05/2021] [Indexed: 12/21/2022]
Abstract
Telomeres are repetitive DNA sequences located at the ends of linear chromosomes that preserve the integrity and stability of the genome. Telomere dysfunctions due to short telomeres or altered telomere structures can ultimately lead to replicative cellular senescence and chromosomal instability, both mechanisms being hallmarks of ageing. Chronic inflammation, oxidative stress and finally telomere length (TL) dynamics have been shown to be involved in various age-related non-communicable diseases (NCDs). Immune-mediated inflammatory diseases (IMIDs), including affections such as inflammatory bowel disease, psoriasis, rheumatoid arthritis, spondyloarthritis and uveitis belong to this group of age-related NCDs. Although in recent years, we have witnessed the emergence of studies in the literature linking these IMIDs to TL dynamics, the causality between these diseases and telomere attrition is still unclear and controversial. In this review, we provide an overview of available studies on telomere dynamics and discuss the utility of TL measurements in immune-mediated inflammatory diseases.
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Colicino E, Cowell W, Bozack A, Foppa Pedretti N, Joshi A, Niedzwiecki MM, Bollati V, Berin C, Wright RO, Wright RJ. Association between prenatal immune phenotyping and cord blood leukocyte telomere length in the PRISM pregnancy cohort. ENVIRONMENTAL RESEARCH 2020; 191:110113. [PMID: 32841635 PMCID: PMC7883408 DOI: 10.1016/j.envres.2020.110113] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 07/28/2020] [Accepted: 08/16/2020] [Indexed: 05/07/2023]
Abstract
BACKGROUND Environmental exposures including air pollutants, toxic metals, and psychosocial stress have been associated with shorter telomere length (TL) in newborns. These exposures have in turn been linked to an enhanced inflammatory immune response. Increased inflammation during pregnancy may be a central biological pathway linking environmental factors with reduced TL at birth. Approaches that more comprehensively characterize the prenatal inflammatory milieu rather than targeting specific individual cytokines in relation to newborn TL may better elucidate inflammatory mechanisms. METHODS Analyses included 129 mother-child dyads enrolled in the PRogramming of Intergenerational Stress Mechanisms (PRISM) pregnancy cohort. We measured 92 inflammation related proteins during pregnancy in maternal serum using the Olink protein array and quantified cord blood relative leukocyte TL (rLTL) via qPCR. We leveraged a tree-based machine learning algorithm to select the most important inflammatory related proteins jointly associated with rLTL. We then evaluated the combined association between the selected proteins with rLTL using Bayesian Weighted Quantile Sum (BWQS) Regression. Analyses were adjusted for gestational week of serum collection, maternal race/ethnicity, age, and education, and fetal sex. We evaluated major biological function of the identified proteins by using the UniProtKB, a centralized repository of curated functional information. RESULTS Three proteins were negatively and linearly associated with rLTL (CASP8 β: -0.22 p = 0.008, BNGF β: -0.43 p = 0.033, TRANCE β: 0.38 p = 0.004). Results from BWQS regression showed a significant overall decrease in rLTL (β: -0.26 95%CrI: -0.43, -0.07) per quartile increase of the mixture, with CASP8 contributing the greatest weight (CASP8 50%; BNGF 27%, and TRANCE 23%). The identified proteins were involved in the regulation of apoptotic processes and cell proliferation. CONCLUSIONS This proteomics approach identifies novel maternal prenatal inflammatory protein biomarkers associated with shortened rLTL in newborns.
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Affiliation(s)
- E Colicino
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| | - W Cowell
- Department of Pediatrics, Kravis Children's Hospital, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - A Bozack
- Department of Pediatrics, Kravis Children's Hospital, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - N Foppa Pedretti
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - A Joshi
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - M M Niedzwiecki
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - C Berin
- Department of Pediatrics, Kravis Children's Hospital, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - R O Wright
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Department of Pediatrics, Kravis Children's Hospital, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - R J Wright
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Department of Pediatrics, Kravis Children's Hospital, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Institute for Exposomic Research, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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7
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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.
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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
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8
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Hyun DH. Plasma membrane redox enzymes: new therapeutic targets for neurodegenerative diseases. Arch Pharm Res 2019; 42:436-445. [PMID: 30919268 DOI: 10.1007/s12272-019-01147-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 03/16/2019] [Indexed: 01/06/2023]
Abstract
Mitochondrial dysfunction caused by oxidative stress appears at early stages of aging and age-related diseases. Plasma membrane redox enzymes act in a compensatory manner to decrease oxidative stress and supply reductive capacity to ensure cell survival. Plasma membrane redox enzymes transfer electrons from NAD(P)H to oxidized ubiquinone and α-tocopherol, resulting in inhibition of further oxidative damage. Plasma membrane redox enzymes and their partners are affected by aging, leading to progression of neurodegenerative disease pathogenesis. Up-regulating plasma membrane redox enzymes via calorie restriction and phytochemicals make cells more resistant to oxidative damage under stress conditions by maintaining redox homeostasis and improving mitochondrial function. Investigation into plasma membrane redox enzymes can provide mechanistic details underlying the relationships between plasma membrane redox enzymes and mitochondrial complexes and provide a good therapeutic target for prevention and delay of neurodegenerative disorders.
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Affiliation(s)
- Dong-Hoon Hyun
- Department of Life Science, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-gu, Seoul, 03760, South Korea.
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Genetic Determinants of Telomere Length in African American Youth. Sci Rep 2018; 8:13265. [PMID: 30185882 PMCID: PMC6125592 DOI: 10.1038/s41598-018-31238-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 08/06/2018] [Indexed: 12/17/2022] Open
Abstract
Telomere length (TL) is associated with numerous disease states and is affected by genetic and environmental factors. However, TL has been mostly studied in adult populations of European or Asian ancestry. These studies have identified 34 TL-associated genetic variants recently used as genetic proxies for TL. The generalizability of these associations to pediatric populations and racially diverse populations, specifically of African ancestry, remains unclear. Furthermore, six novel variants associated with TL in a population of European children have been identified but not validated. We measured TL from whole blood samples of 492 healthy African American youth (children and adolescents between 8 and 20 years old) and performed the first genome-wide association study of TL in this population. We were unable to replicate neither the 34 reported genetic associations found in adults nor the six genetic associations found in European children. However, we discovered a novel genome-wide significant association between TL and rs1483898 on chromosome 14. Our results underscore the importance of examining genetic associations with TL in diverse pediatric populations such as African Americans.
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Otsuka K, Suzuki K, Fujimichi Y, Tomita M, Iwasaki T. Cellular responses and gene expression profiles of colonic Lgr5+ stem cells after low-dose/low-dose-rate radiation exposure. JOURNAL OF RADIATION RESEARCH 2018; 59:ii18-ii22. [PMID: 29281035 PMCID: PMC5941159 DOI: 10.1093/jrr/rrx078] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/13/2017] [Indexed: 06/07/2023]
Abstract
We previously found that high-dose-rate radiation induced a replenishment of the colonic Lgr5+ stem cell pool, whereas low-dose-rate radiation did not. To identify key molecules that determine the dose-rate effects on this stem cell pool, we harvested colonic Lgr5+ stem cells by cell sorting at 2 weeks after exposure to 1 Gy of high-dose-rate (30 Gy/h) or low-dose-rate (0.003 Gy/h) radiation and analyzed their gene expression profiles using RNA-Seq. We found that pathways related to DNA damage response, cell growth, cell differentiation and cell death were upregulated in Lgr5+ stem cells irradiated with high dose rates, whereas pathways related to apical junctions and extracellular signaling were upregulated in low-dose-rate-irradiated colonic Lgr5+ stem cells. Interestingly, biological events involving apical junctions are known to play an important role in the exclusion of transformed cells that are surrounded by normal epithelial cells through 'cell competition'. We speculated that cell competition, through apical junctions and extracellular ligands, might contribute to the dose-rate effect on Lgr5+ cell replenishment. To understand this mechanism, we focused on 69 genes that were significantly upregulated in low-dose-rate-irradiated cells, which we named DREDGE (Dose-Rate Effect Determining GEnes). Based on these findings, we propose a possible mechanism underlying the dose-rate effect observed in the colonic stem cell pool.
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Affiliation(s)
- Kensuke Otsuka
- Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwado-kita, Komae, Tokyo 201-8511, Japan
| | - Keiji Suzuki
- Department of Radiation Medical Sciences, Atomic Bomb Disease Institute, Nagasaki University, Nagasaki, Japan
| | - Yuki Fujimichi
- Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwado-kita, Komae, Tokyo 201-8511, Japan
| | - Masanori Tomita
- Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwado-kita, Komae, Tokyo 201-8511, Japan
| | - Toshiyasu Iwasaki
- Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwado-kita, Komae, Tokyo 201-8511, Japan
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11
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Snetselaar R, van Batenburg AA, van Oosterhout MFM, Kazemier KM, Roothaan SM, Peeters T, van der Vis JJ, Goldschmeding R, Grutters JC, van Moorsel CHM. Short telomere length in IPF lung associates with fibrotic lesions and predicts survival. PLoS One 2017; 12:e0189467. [PMID: 29281671 PMCID: PMC5744955 DOI: 10.1371/journal.pone.0189467] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 11/28/2017] [Indexed: 12/15/2022] Open
Abstract
Telomere maintenance dysfunction has been implicated in the pathogenesis of Idiopathic Pulmonary Fibrosis (IPF). However, the mechanism of how telomere length is related to fibrosis in the lungs is unknown. Surgical lung biopsies of IPF patients typically show a heterogeneous pattern of non-fibrotic and fibrotic areas. Therefore, telomere length (TL) in both lung areas of patients with IPF and familial interstitial pneumonia was compared, specifically in alveolar type 2 (AT2) cells. Fluorescent in situ hybridization was used to determine TL in non-fibrotic and fibrotic areas of 35 subjects. Monochrome multiplex quantitative polymerase chain reaction (MMqPCR) was used for 51 whole lung biopsies and blood TL measurements. For sporadic IPF subjects, AT2 cell TL in non-fibrotic areas was 56% longer than in fibrotic areas. No such difference was observed in the surrounding lung cells. In subjects carrying a telomerase reverse transcriptase (TERT) mutation, AT2 cell TL was significantly shorter than in sporadic subjects. However, no difference in surrounding cell TL was observed between these subject groups. Finally, using biopsy MMqPCR TL measurements, it was determined that IPF subjects with shortest lung TL had a significantly worse survival than patients with long TL. This study shows that shortening of telomeres critically affects AT2 cells in fibrotic areas, implying TL as a cause of fibrogenesis. Furthermore, short lung telomere length is associated with decreased survival.
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Affiliation(s)
- Reinier Snetselaar
- Department of Pulmonology, St Antonius ILD Center of Excellence, St Antonius Hospital, Nieuwegein, the Netherlands
| | - Aernoud A. van Batenburg
- Department of Pulmonology, St Antonius ILD Center of Excellence, St Antonius Hospital, Nieuwegein, the Netherlands
| | | | - Karin M. Kazemier
- Department of Pulmonology, St Antonius ILD Center of Excellence, St Antonius Hospital, Nieuwegein, the Netherlands
- Division of Heart and Lungs, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Suzan M. Roothaan
- Department of Pathology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Ton Peeters
- Department of Pathology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Joanne J. van der Vis
- Department of Pulmonology, St Antonius ILD Center of Excellence, St Antonius Hospital, Nieuwegein, the Netherlands
- Department of Clinical Chemistry, St Antonius ILD Center of Excellence, St Antonius Hospital, Nieuwegein, the Netherlands
| | - Roel Goldschmeding
- Department of Pathology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Jan C. Grutters
- Department of Pulmonology, St Antonius ILD Center of Excellence, St Antonius Hospital, Nieuwegein, the Netherlands
- Division of Heart and Lungs, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Coline H. M. van Moorsel
- Department of Pulmonology, St Antonius ILD Center of Excellence, St Antonius Hospital, Nieuwegein, the Netherlands
- Division of Heart and Lungs, University Medical Center Utrecht, Utrecht, the Netherlands
- * E-mail:
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12
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Interaction studies of carbon nanomaterials and plasma activated carbon nanomaterials solution with telomere binding protein. Sci Rep 2017; 7:2636. [PMID: 28572671 PMCID: PMC5454022 DOI: 10.1038/s41598-017-02690-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 04/13/2017] [Indexed: 11/21/2022] Open
Abstract
Most cancer cells have telomerase activity because they can express the human telomerase reverse transcriptase (hTERT) gene. Therefore, the inhibition of the hTERT expression can play an important role in controlling cancer cell proliferation. Our current study aims to inhibit hTERT expression. For this, we synthesized graphene oxide (GO) and a functionalized multiwall carbon nanotube (f-MWCNT), latter treated them with cold atmospheric pressure plasma for further analysis of the hTERT expression. The inhibition of hTERT expression by GO, f-MWCNT, plasma activated GO solution (PGOS), and plasma activated f-MWCNT solution (PCNTS), was studied using two lung cancer cell lines, A549 and H460. The hTERT experimental results revealed that GO and PGOS sufficiently decreased the hTERT concentration, while f-MWCNT and PCNTS were unable to inhibit the hTERT concentration. Therefore, to understand the inhibition mechanism of hTERT, we studied the binding properties of GO and PGOS with telomere binding protein (AtTRB2). The interaction studies were carried out using circular dichroism, fluorescence, 1H-15N NMR spectroscopy, and size-exclusion chromatography (SEC) binding assay. We also used docking simulation to have an better understanding of the interactions between GO nanosheets and AtTRB2 protein. Our results may provide new insights that can benefit in biomedical treatments.
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Cultured human amniocytes express hTERT, which is distributed between nucleus and cytoplasm and is secreted in extracellular vesicles. Biochem Biophys Res Commun 2016; 483:706-711. [PMID: 27988335 DOI: 10.1016/j.bbrc.2016.12.077] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 12/11/2016] [Indexed: 12/20/2022]
Abstract
BACKGROUND An increasing number of studies on stem cells suggests that the therapeutic effect they exert is primarily mediated by a paracrine regulation through extracellular vesicles (EVs) giving solid grounds for stem cell EVs to be exploited as agents for treating diseases or for restoring damaged tissues and organs. Due to their capacity to differentiate in all embryonic germ layers, amniotic fluid stem cells (AFCs), represent a highly promising cell type for tissue regeneration, which however is still poorly studied and in turn underutilized. In view of this, we conducted a first investigation on the expression of human hTERT gene - known to be among the key triggers of organ regeneration - in AFCs and in the EVs they secrete. METHODS Isolated AFCs were evaluated by RT-qPCR for hTERT expression. The clones expressing the highest levels of transcript, were analyzed by Immunofluorescence imaging and Nuclear/cytoplasmic fractionation in order to evaluate hTERT subcellular localization. We then separated EVs from FBS depleted culture medium by serial (ultra) centrifugations steps and characterized them using Western blotting, Atomic force Microscopy and Nanoplasmonic assay. RESULTS We first demonstrated that primary cultures of AFCs express the gene hTERT at different levels. Then we evidenced that in AFCs with the higher transcript levels, the hTERT protein is present in the nuclear and cytoplasmic compartment. Finally, we found that cytosolic hTERT is embodied in the EVs that AFCs secrete in the extracellular milieu. CONCLUSIONS Our study demonstrates for the first time the expression of the full protein hTERT by AFCs and its release outside the cell mediated by EVs, indicating a new extra telomeric role for this protein. This finding represents an initial but crucial evidence for considering AFCs derived EVs as new potential sources for tissue regeneration.
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Nurkovic J, Volarevic V, Lako M, Armstrong L, Arsenijevic N, Stojkovic M. Aging of Stem and Progenitor Cells: Mechanisms, Impact on Therapeutic Potential, and Rejuvenation. Rejuvenation Res 2016; 19:3-12. [PMID: 26055182 DOI: 10.1089/rej.2015.1676] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
It was once suggested that adult or tissue-specific stem cells may be immortal; however, several recently published data suggest that their efficacy is limited by natural aging in common with most other somatic cell types. Decreased activity of stem cells in old age raises questions as to whether the age of the donor should be considered during stem cell transplantation and at what age the donor stem cells should be harvested to ensure the largest possible number of viable, functional, and non-altered stem cells. Although stem cells remain active into old age, changes in stem cells and their microenvironments inhibit their regenerative potential. The impact of aging on stem cell populations differs between tissues and depends on a number intrinsic and extrinsic factors, including systemic changes associated with immune system alterations. In this review, we describe key mechanisms of stem and progenitor cell aging and techniques that are currently used to identify signs of stem cells aging. Furthermore, we focus on the impact of aging on the capacity for proliferation, differentiation, and clinical use of stem cells. Finally, we detail the aging of embryonic, mesenchymal, and induced pluripotent stem cells, with particular emphasis on aging mechanisms and rejuvenation.
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Affiliation(s)
- Jasmin Nurkovic
- 1 Stem Cell Laboratory, Department of Biomedical Sciences, State University of Novi Pazar , Novi Pazar, Serbia
| | - Vladislav Volarevic
- 2 Centre for Molecular Medicine and Stem Cell Research, Faculty of Medical Sciences, University of Kragujevac , Kragujevac, Serbia
| | - Majlinda Lako
- 3 Institute of Genetic Medicine, International Centre for Life, Newcastle University , Newcastle upon Tyne, United Kingdom
| | - Lyle Armstrong
- 3 Institute of Genetic Medicine, International Centre for Life, Newcastle University , Newcastle upon Tyne, United Kingdom
| | - Nebojsa Arsenijevic
- 2 Centre for Molecular Medicine and Stem Cell Research, Faculty of Medical Sciences, University of Kragujevac , Kragujevac, Serbia
| | - Miodrag Stojkovic
- 2 Centre for Molecular Medicine and Stem Cell Research, Faculty of Medical Sciences, University of Kragujevac , Kragujevac, Serbia .,4 Spebo Medical , Leskovac, Serbia
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15
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The Telomere/Telomerase System in Chronic Inflammatory Diseases. Cause or Effect? Genes (Basel) 2016; 7:genes7090060. [PMID: 27598205 PMCID: PMC5042391 DOI: 10.3390/genes7090060] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 07/26/2016] [Accepted: 08/29/2016] [Indexed: 12/23/2022] Open
Abstract
Telomeres are specialized nucleoprotein structures located at the end of linear chromosomes and telomerase is the enzyme responsible for telomere elongation. Telomerase activity is a key component of many cancer cells responsible for rapid cell division but it has also been found by many laboratories around the world that telomere/telomerase biology is dysfunctional in many other chronic conditions as well. These conditions are characterized by chronic inflammation, a situation mostly overlooked by physicians regarding patient treatment. Among others, these conditions include diabetes, renal failure, chronic obstructive pulmonary disease, etc. Since researchers have in many cases identified the association between telomerase and inflammation but there are still many missing links regarding this correlation, the latest findings about this phenomenon will be discussed by reviewing the literature. Our focus will be describing telomere/telomerase status in chronic diseases under the prism of inflammation, reporting molecular findings where available and proposing possible future approaches.
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16
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Cho SJ, Koo J, Chun KH, Cha HJ. Control of stress signaling in stem cells: crossroads of stem cells and cancer. Tumour Biol 2016; 37:12983-12990. [PMID: 27460084 DOI: 10.1007/s13277-016-5249-x] [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: 04/10/2016] [Accepted: 07/15/2016] [Indexed: 10/21/2022] Open
Abstract
Tumorigenesis is a relatively rare event in the human body considering the enormous number of cells composing our body and the frequent occurrence of genetic mutations in each cell. Nevertheless, the cells that happen to meet the minimum requirements can be transformed when stressed by a variety of oncogenic stimulations, then progress to form tumors. The vigorous competition between oncogenic signaling and tumor-suppressor defense is a critical determinant of cellular fate, which can be either tumorigenic transformation or cellular senescence/apoptosis depending on "who wins the battle." Recently, a number of cancers have been reported to originate from stem cells, whose self-renewing properties are normally reduced by innate tumor suppressors. Therefore, exploring the innate mechanism by which stem cells modulate tumor suppressors to maintain their "stemness" may provide valuable clues to characterize the distinctive oncogenic susceptibility of stem cells. This review is focused on the recent advances in the field of tumorigenesis of stem cells and on the associated molecular mechanisms.
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Affiliation(s)
- Seung-Ju Cho
- Department of Life Sciences, Sogang University, Seoul, 04107, South Korea
| | - JaeHyung Koo
- Department of Brain and Cognitive Sciences, DGIST, Daegu, South Korea
| | - Kwang-Hoon Chun
- Gachon Institute of Pharmaceutical Sciences, College of Pharmacy, Gachon University, Incheon, 21936, South Korea
| | - Hyuk-Jin Cha
- Department of Life Sciences, Sogang University, Seoul, 04107, South Korea.
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17
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Scherthan H, Sotnik N, Peper M, Schrock G, Azizova T, Abend M. Telomere Length in Aged Mayak PA Nuclear Workers Chronically Exposed to Internal Alpha and External Gamma Radiation. Radiat Res 2016; 185:658-67. [DOI: 10.1667/rr14271.1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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18
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Bednarek D, González-Rosa JM, Guzmán-Martínez G, Gutiérrez-Gutiérrez Ó, Aguado T, Sánchez-Ferrer C, Marques IJ, Galardi-Castilla M, de Diego I, Gómez MJ, Cortés A, Zapata A, Jiménez-Borreguero LJ, Mercader N, Flores I. Telomerase Is Essential for Zebrafish Heart Regeneration. Cell Rep 2015; 12:1691-703. [PMID: 26321646 PMCID: PMC4589159 DOI: 10.1016/j.celrep.2015.07.064] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 05/27/2015] [Accepted: 07/29/2015] [Indexed: 11/05/2022] Open
Abstract
After myocardial infarction in humans, lost cardiomyocytes are replaced by an irreversible fibrotic scar. In contrast, zebrafish hearts efficiently regenerate after injury. Complete regeneration of the zebrafish heart is driven by the strong proliferation response of its cardiomyocytes to injury. Here we show that, after cardiac injury in zebrafish, telomerase becomes hyperactivated, and telomeres elongate transiently, preceding a peak of cardiomyocyte proliferation and full organ recovery. Using a telomerase-mutant zebrafish model, we found that telomerase loss drastically decreases cardiomyocyte proliferation and fibrotic tissue regression after cryoinjury and that cardiac function does not recover. The impaired cardiomyocyte proliferation response is accompanied by the absence of cardiomyocytes with long telomeres and an increased proportion of cardiomyocytes showing DNA damage and senescence characteristics. These findings demonstrate the importance of telomerase function in heart regeneration and highlight the potential of telomerase therapy as a means of stimulating cell proliferation upon myocardial infarction.
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Affiliation(s)
- Dorota Bednarek
- Regeneration and Aging Group, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Juan Manuel González-Rosa
- Development of the Epicardium and Its Role during Regeneration Group, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Gabriela Guzmán-Martínez
- Cardiovascular Imaging in Humans, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Óscar Gutiérrez-Gutiérrez
- Regeneration and Aging Group, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Tania Aguado
- Regeneration and Aging Group, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Carlota Sánchez-Ferrer
- Regeneration and Aging Group, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Inês João Marques
- Development of the Epicardium and Its Role during Regeneration Group, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - María Galardi-Castilla
- Development of the Epicardium and Its Role during Regeneration Group, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Irene de Diego
- Regeneration and Aging Group, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Manuel José Gómez
- Bioinformatic Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Alfonso Cortés
- Electron Microscopy Center, Complutense University, Madrid 28040, Spain
| | - Agustín Zapata
- Electron Microscopy Center, Complutense University, Madrid 28040, Spain
| | - Luis Jesús Jiménez-Borreguero
- Cardiovascular Imaging in Humans, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain
| | - Nadia Mercader
- Development of the Epicardium and Its Role during Regeneration Group, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain.
| | - Ignacio Flores
- Regeneration and Aging Group, Centro Nacional de Investigaciones Cardiovasculares (CNIC-ISCIII), Melchor Fernández Almagro 3, 28029 Madrid, Spain.
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Abstract
Despite the increasing use of stem cells for regenerative-based cardiac therapy, the optimal stem cell population(s) remains in a cloud of uncertainty. In the past decade, the field has witnessed a surge of researchers discovering stem cell populations reported to directly and/or indirectly contribute to cardiac regeneration through processes of cardiomyogenic commitment and/or release of cardioprotective paracrine factors. This review centers upon defining basic biological characteristics of stem cells used for sustaining cardiac integrity during disease and maintenance of communication between the cardiac environment and stem cells. Given the limited successes achieved so far in regenerative therapy, the future requires development of unprecedented concepts involving combinatorial approaches to create and deliver the optimal stem cell(s) that will enhance myocardial healing.
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Affiliation(s)
- Pearl Quijada
- Integrated Regenerative Research Institute, Department of Biology, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, USA
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20
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Otsuka K, Iwasaki T. Effects of dose rates on radiation-induced replenishment of intestinal stem cells determined by Lgr5 lineage tracing. JOURNAL OF RADIATION RESEARCH 2015; 56:615-22. [PMID: 25832104 PMCID: PMC4497386 DOI: 10.1093/jrr/rrv012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 02/16/2015] [Indexed: 05/05/2023]
Abstract
An understanding of the dynamics of intestinal Lgr5(+) stem cells is important for elucidating the mechanism of colonic cancer development. We previously established a method for evaluating Lgr5(+) stem cells by tamoxifen-dependent Lgr5-lineage tracing and showed that high-dose-rate radiation stimulated replenishment of colonic stem cells. In this study, we evaluated the effects of low-dose-rate radiation on stem cell maintenance. Tamoxifen (4OHT)-injected Lgr5-EGFP-IRES-Cre(ERT2) × ROSA-LSL-LacZ mice were used, LacZ-labeled colonic crypts were enumerated, and the loss of LacZ(+) crypts under low-dose-rate radiation was estimated. After 4OHT treatment, the number of LacZ-labeled Lgr5(+) stem cells was higher in the colon of infant mice than in adult mice. The percentage of LacZ-labeled crypts in infant mice rapidly decreased after 4OHT treatment. However, the percentage of labeled crypts plateaued at ∼2% at 4 weeks post-treatment and remained unchanged for up to 7 months. Thus, it will be advantageous to evaluate the long-term effects of low-dose-rate radiation. Next, we determined the percentages of LacZ-labeled crypts irradiated with 1 Gy administered at different dose rates. As reported in our previous study, mice exposed to high-dose-rate radiation (30 Gy/h) showed a marked replenishment (P = 0.04). However, mice exposed to low-dose-rate radiation (0.003 Gy/h) did not exhibit accelerated stem-cell replenishment (P = 0.47). These findings suggest the percentage of labeled crypts can serve as a useful indicator of the effects of dose rate on the stem cell pool.
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Affiliation(s)
- Kensuke Otsuka
- Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwado-kita, Komae, Tokyo 201-8511, Japan
| | - Toshiyasu Iwasaki
- Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwado-kita, Komae, Tokyo 201-8511, Japan
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21
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Trochet D, Mergui X, Ivkovic I, Porreca RM, Gerbault-Seureau M, Sidibe A, Richard F, Londono-Vallejo A, Perret M, Aujard F, Riou JF. Telomere regulation during ageing and tumorigenesis of the grey mouse lemur. Biochimie 2015; 113:100-10. [PMID: 25882681 DOI: 10.1016/j.biochi.2015.04.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 04/03/2015] [Indexed: 01/01/2023]
Abstract
Telomere erosion leading to replicative senescence has been well documented in human and anthropoid primates, and provides a clue against tumorigenesis. In contrast, other mammals, such as laboratory mice, with short lifespan and low body weight mass have different telomere biology without replicative senescence. We analyzed telomere biology in the grey mouse lemur, a small prosimian model with a relative long lifespan currently used in ageing research. We report an average telomere length by telomere restriction fragment (TRF) among the longest reported so far for a primate species (25-30 kb), but without detectable overall telomere shortening with ageing on blood samples. However, we demonstrate using universal STELA (Single Telomere Length Amplification) the existence of short telomeres, the increase of which, while correlating with ageing might be related to another mechanism than replicative senescence. We also found a low stringency of telomerase restriction in tissues and an ease to immortalize fibroblasts in vitro upon spontaneous telomerase activation. Finally, we describe the first grey mouse lemur cancer cell line showing a dramatic telomere shortening and high telomerase activity associated with polyploidy. Our overall results suggest that telomere biology in grey mouse lemur is an exception among primates, with at best a physiologically limited replicative telomere ageing and closest to that observed in small rodents.
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Affiliation(s)
- Delphine Trochet
- Structure et Instabilité des Génomes, Sorbonne Universités, Muséum National d'Histoire Naturelle, Inserm U 1154, CNRS UMR 7196, CP26, 57 rue Cuvier, 75005 Paris, France
| | - Xénia Mergui
- Structure et Instabilité des Génomes, Sorbonne Universités, Muséum National d'Histoire Naturelle, Inserm U 1154, CNRS UMR 7196, CP26, 57 rue Cuvier, 75005 Paris, France
| | - Ivana Ivkovic
- Structure et Instabilité des Génomes, Sorbonne Universités, Muséum National d'Histoire Naturelle, Inserm U 1154, CNRS UMR 7196, CP26, 57 rue Cuvier, 75005 Paris, France
| | - Rosa Maria Porreca
- Telomeres and Cancer Laboratory, CNRS UMR 3244, Institut Curie, 26 rue d'Ulm, 75248 Paris, France; UPMC Univ. Paris 06, 75005 Paris, France
| | - Michèle Gerbault-Seureau
- Institut de Systématique, Evolution, Biodiversité, Sorbonne Universités, Muséum National d'Histoire Naturelle, UMR 7205 CNRS, UPMC Univ. Paris 06, EPHE, 57 rue Cuvier, 75005 Paris, France
| | - Assitan Sidibe
- Structure et Instabilité des Génomes, Sorbonne Universités, Muséum National d'Histoire Naturelle, Inserm U 1154, CNRS UMR 7196, CP26, 57 rue Cuvier, 75005 Paris, France
| | - Florence Richard
- Institut de Systématique, Evolution, Biodiversité, Sorbonne Universités, Muséum National d'Histoire Naturelle, UMR 7205 CNRS, UPMC Univ. Paris 06, EPHE, 57 rue Cuvier, 75005 Paris, France
| | - Arturo Londono-Vallejo
- Telomeres and Cancer Laboratory, CNRS UMR 3244, Institut Curie, 26 rue d'Ulm, 75248 Paris, France; UPMC Univ. Paris 06, 75005 Paris, France
| | - Martine Perret
- Mécanismes Adaptatifs et Evolution, Muséum National d'Histoire Naturelle, Sorbonne Universités, UMR 7179 CNRS, 1 Avenue du Petit Château, 91800 Brunoy, France
| | - Fabienne Aujard
- Mécanismes Adaptatifs et Evolution, Muséum National d'Histoire Naturelle, Sorbonne Universités, UMR 7179 CNRS, 1 Avenue du Petit Château, 91800 Brunoy, France
| | - Jean-François Riou
- Structure et Instabilité des Génomes, Sorbonne Universités, Muséum National d'Histoire Naturelle, Inserm U 1154, CNRS UMR 7196, CP26, 57 rue Cuvier, 75005 Paris, France.
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22
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Li T, Shi Y, Wang P, Guachalla LM, Sun B, Joerss T, Chen YS, Groth M, Krueger A, Platzer M, Yang YG, Rudolph KL, Wang ZQ. Smg6/Est1 licenses embryonic stem cell differentiation via nonsense-mediated mRNA decay. EMBO J 2015; 34:1630-47. [PMID: 25770585 PMCID: PMC4475398 DOI: 10.15252/embj.201489947] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Accepted: 02/18/2015] [Indexed: 12/12/2022] Open
Abstract
Nonsense-mediated mRNA decay (NMD) is a post-transcriptional mechanism that targets aberrant transcripts and regulates the cellular RNA reservoir. Genetic modulation in vertebrates suggests that NMD is critical for cellular and tissue homeostasis, although the underlying mechanism remains elusive. Here, we generate knockout mice lacking Smg6/Est1, a key nuclease in NMD and a telomerase cofactor. While the complete loss of Smg6 causes mouse lethality at the blastocyst stage, inducible deletion of Smg6 is compatible with embryonic stem cell (ESC) proliferation despite the absence of telomere maintenance and functional NMD. Differentiation of Smg6-deficient ESCs is blocked due to sustained expression of pluripotency genes, normally repressed by NMD, and forced down-regulation of one such target, c-Myc, relieves the differentiation block. Smg6-null embryonic fibroblasts are viable as well, but are refractory to cellular reprograming into induced pluripotent stem cells (iPSCs). Finally, depletion of all major NMD factors compromises ESC differentiation, thus identifying NMD as a licensing factor for the switch of cell identity in the process of stem cell differentiation and somatic cell reprograming.
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Affiliation(s)
- Tangliang Li
- Leibniz Institute for Age Research - Fritz Lipmann Institute (FLI), Jena, Germany
| | - Yue Shi
- Disease Genomics and Individualized Medicine Laboratory, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Pei Wang
- Leibniz Institute for Age Research - Fritz Lipmann Institute (FLI), Jena, Germany
| | - Luis Miguel Guachalla
- Institute of Molecular Medicine and Max-Planck-Research Department of Stem Cell Aging, University of Ulm, Ulm, Germany
| | - Baofa Sun
- Disease Genomics and Individualized Medicine Laboratory, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Tjard Joerss
- Leibniz Institute for Age Research - Fritz Lipmann Institute (FLI), Jena, Germany
| | - Yu-Sheng Chen
- Disease Genomics and Individualized Medicine Laboratory, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Marco Groth
- Leibniz Institute for Age Research - Fritz Lipmann Institute (FLI), Jena, Germany
| | - Anja Krueger
- Leibniz Institute for Age Research - Fritz Lipmann Institute (FLI), Jena, Germany
| | - Matthias Platzer
- Leibniz Institute for Age Research - Fritz Lipmann Institute (FLI), Jena, Germany
| | - Yun-Gui Yang
- Disease Genomics and Individualized Medicine Laboratory, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Karl Lenhard Rudolph
- Leibniz Institute for Age Research - Fritz Lipmann Institute (FLI), Jena, Germany Institute of Molecular Medicine and Max-Planck-Research Department of Stem Cell Aging, University of Ulm, Ulm, Germany
| | - Zhao-Qi Wang
- Leibniz Institute for Age Research - Fritz Lipmann Institute (FLI), Jena, Germany Faculty of Biology and Pharmacy, Friedrich-Schiller University of Jena, Jena, Germany
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23
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Sepúlveda JC, Tomé M, Fernández ME, Delgado M, Campisi J, Bernad A, González MA. Cell senescence abrogates the therapeutic potential of human mesenchymal stem cells in the lethal endotoxemia model. Stem Cells 2015; 32:1865-77. [PMID: 24496748 DOI: 10.1002/stem.1654] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 01/12/2014] [Indexed: 01/01/2023]
Abstract
Mesenchymal stem cells (MSCs) possess unique paracrine and immunosuppressive properties, which make them useful candidates for cellular therapy. Here, we address how cellular senescence influences the therapeutic potential of human MSCs (hMSCs). Senescence was induced in bone marrow-derived hMSC cultures with gamma irradiation. Control and senescent cells were tested for their immunoregulatory activity in vitro and in vivo, and an extensive molecular characterization of the phenotypic changes induced by senescence was performed. We also compared the gene expression profiles of senescent hMSCs with a collection of hMSCs used in an ongoing clinical study of Graft Versus Host disease (GVHD). Our results show that senescence induces extensive phenotypic changes in hMSCs and abrogates their protective activity in a murine model of LPS-induced lethal endotoxemia. Although senescent hMSCs retain an ability to regulate the inflammatory response on macrophages in vitro, and, in part retain their capacity to significantly inhibit lymphocyte proliferation, they have a severely impaired migratory capacity in response to proinflammatory signals, which is associated with an inhibition of the AP-1 pathway. Additionally, expression analysis identified PLEC, C8orf48, TRPC4, and ZNF14, as differentially regulated genes in senescent hMSCs that were similarly regulated in those hMSCs which failed to produce a therapeutic effect in a GVHD trial. All the observed phenotypic alterations were confirmed in replicative-senescent hMSCs. In conclusion, this study highlights important changes in the immunomodulatory phenotype of senescent hMSCs and provides candidate gene signatures which may be useful to evaluate the therapeutic potential of hMSCs used in future clinical studies.
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Affiliation(s)
- Juan Carlos Sepúlveda
- Department of Cardiovascular Development and Repair, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
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24
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Tao S, Tang D, Morita Y, Sperka T, Omrani O, Lechel A, Sakk V, Kraus J, Kestler HA, Kühl M, Rudolph KL. Wnt activity and basal niche position sensitize intestinal stem and progenitor cells to DNA damage. EMBO J 2015; 34:624-40. [PMID: 25609789 PMCID: PMC4365032 DOI: 10.15252/embj.201490700] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Aging and carcinogenesis coincide with the accumulation of DNA damage and mutations in stem and progenitor cells. Molecular mechanisms that influence responses of stem and progenitor cells to DNA damage remain to be delineated. Here, we show that niche positioning and Wnt signaling activity modulate the sensitivity of intestinal stem and progenitor cells (ISPCs) to DNA damage. ISPCs at the crypt bottom with high Wnt/β-catenin activity are more sensitive to DNA damage compared to ISPCs in position 4 with low Wnt activity. These differences are not induced by differences in cell cycle activity but relate to DNA damage-dependent activation of Wnt signaling, which in turn amplifies DNA damage checkpoint activation. The study shows that instructed enhancement of Wnt signaling increases radio-sensitivity of ISPCs, while inhibition of Wnt signaling decreases it. These results provide a proof of concept that cell intrinsic levels of Wnt signaling modulate the sensitivity of ISPCs to DNA damage and heterogeneity in Wnt activation in the stem cell niche contributes to the selection of ISPCs in the context of DNA damage.
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Affiliation(s)
- Si Tao
- Leibniz Institute for Age Research - Fritz Lipmann Institute e.V. (FLI), Jena, Germany Institute of Biochemistry and Molecular Biology, Ulm University, Ulm, Germany International Graduate School in Molecular Medicine Ulm, Ulm University, Ulm, Germany
| | - Duozhuang Tang
- Leibniz Institute for Age Research - Fritz Lipmann Institute e.V. (FLI), Jena, Germany
| | - Yohei Morita
- Leibniz Institute for Age Research - Fritz Lipmann Institute e.V. (FLI), Jena, Germany
| | - Tobias Sperka
- Leibniz Institute for Age Research - Fritz Lipmann Institute e.V. (FLI), Jena, Germany
| | - Omid Omrani
- Leibniz Institute for Age Research - Fritz Lipmann Institute e.V. (FLI), Jena, Germany
| | - André Lechel
- Cooperation Group between the Leibniz Institute for Age Research, Ulm University, Ulm, Germany
| | - Vadim Sakk
- Cooperation Group between the Leibniz Institute for Age Research, Ulm University, Ulm, Germany
| | - Johann Kraus
- Medical Systems Biology Unit, Ulm University, Ulm, Germany
| | - Hans A Kestler
- Leibniz Institute for Age Research - Fritz Lipmann Institute e.V. (FLI), Jena, Germany Medical Systems Biology Unit, Ulm University, Ulm, Germany
| | - Michael Kühl
- Institute of Biochemistry and Molecular Biology, Ulm University, Ulm, Germany
| | - Karl Lenhard Rudolph
- Leibniz Institute for Age Research - Fritz Lipmann Institute e.V. (FLI), Jena, Germany Research Group on Stem Cell Aging, Jena University Hospital (UKJ), Jena, Germany
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25
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Boraschi D, Italiani P. Immunosenescence and vaccine failure in the elderly: Strategies for improving response. Immunol Lett 2014; 162:346-53. [DOI: 10.1016/j.imlet.2014.06.006] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 06/09/2014] [Accepted: 06/12/2014] [Indexed: 12/21/2022]
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Rossiello F, Herbig U, Longhese MP, Fumagalli M, d'Adda di Fagagna F. Irreparable telomeric DNA damage and persistent DDR signalling as a shared causative mechanism of cellular senescence and ageing. Curr Opin Genet Dev 2014; 26:89-95. [PMID: 25104620 PMCID: PMC4217147 DOI: 10.1016/j.gde.2014.06.009] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 06/22/2014] [Accepted: 06/25/2014] [Indexed: 12/13/2022]
Abstract
The DNA damage response (DDR) orchestrates DNA repair and halts cell cycle. If damage is not resolved, cells can enter into an irreversible state of proliferative arrest called cellular senescence. Organismal ageing in mammals is associated with accumulation of markers of cellular senescence and DDR persistence at telomeres. Since the vast majority of the cells in mammals are non-proliferating, how do they age? Are telomeres involved? Also oncogene activation causes cellular senescence due to altered DNA replication and DDR activation in particular at the telomeres. Is there a common mechanism shared among apparently distinct types of cellular senescence? And what is the role of telomeric DNA damage?
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Affiliation(s)
- Francesca Rossiello
- IFOM Foundation - FIRC Institute of Molecular Oncology Foundation, Milan 20139, Italy
| | - Utz Herbig
- Department of Microbiology and Molecular Genetics, New Jersey Medical School - Cancer Center, Rutgers Biomedical and Health Sciences, Rutgers University, Newark, NJ 07103, USA
| | - Maria Pia Longhese
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan 20126, Italy
| | - Marzia Fumagalli
- IFOM Foundation - FIRC Institute of Molecular Oncology Foundation, Milan 20139, Italy
| | - Fabrizio d'Adda di Fagagna
- IFOM Foundation - FIRC Institute of Molecular Oncology Foundation, Milan 20139, Italy; Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche, Pavia 27100, Italy.
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27
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Rando TA, Wyss-Coray T. Stem cells as vehicles for youthful regeneration of aged tissues. J Gerontol A Biol Sci Med Sci 2014; 69 Suppl 1:S39-42. [PMID: 24833585 DOI: 10.1093/gerona/glu043] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Stem cells hold great promise for regenerative therapies for a wide spectrum of diseases and disorders of aging by virtue of their ability to regenerate tissues and contribute to their homeostasis. Aging is associated with a marked decline in these functionalities of adult stem cells. As such, regeneration of aged tissues is both less efficient and less effective than that of young tissues. Recent studies have revealed the remarkably dynamic responses of stem cells to systemic signals, including the ability of "youthful" factors in the blood of young animals to enhance the functionality of aged stem cells. Thus, there is much hope that even aged stem cells retain a remarkable regenerative potential if provided with the correct cues and environment to engage in tissue repair. The overall focus of the presentations of this session is to address the determinants of changes in stem cell functionality with age, the key characteristics of stem cells in aged tissues, the extent to which those characteristics are capable of being rejuvenated and by what signals, and the potential for stem cell therapeutics for chronic diseases and acute injuries in aged individuals.
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Affiliation(s)
- Thomas A Rando
- Paul F. Glenn Laboratories for the Biology of Aging and Department of Neurology and Neurological Sciences, Stanford University School of Medicine, California. Rehabilitation R&D Program, REAP, VA Palo Alto Health Care System, Palo Alto, California.
| | - Tony Wyss-Coray
- Rehabilitation R&D Program, REAP, VA Palo Alto Health Care System, Palo Alto, California. Department of Neurology and Neurological Sciences, Stanford University, California
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28
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Recombinogenic telomeres in diploid Sorex granarius (Soricidae, Eulipotyphla) fibroblast cells. Mol Cell Biol 2014; 34:2786-99. [PMID: 24842907 DOI: 10.1128/mcb.01697-13] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The telomere structure in the Iberian shrew Sorex granarius is characterized by unique, striking features, with short arms of acrocentric chromosomes carrying extremely long telomeres (up to 300 kb) with interspersed ribosomal DNA (rDNA) repeat blocks. In this work, we investigated the telomere physiology of S. granarius fibroblast cells and found that telomere repeats are transcribed on both strands and that there is no telomere-dependent senescence mechanism. Although telomerase activity is detectable throughout cell culture and appears to act on both short and long telomeres, we also discovered that signatures of a recombinogenic activity are omnipresent, including telomere-sister chromatid exchanges, formation of alternative lengthening of telomeres (ALT)-associated PML-like bodies, production of telomere circles, and a high frequency of telomeres carrying marks of a DNA damage response. Our results suggest that recombination participates in the maintenance of the very long telomeres in normal S. granarius fibroblasts. We discuss the possible interplay between the interspersed telomere and rDNA repeats in the stabilization of the very long telomeres in this organism.
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29
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Do telomeres adapt to physiological stress? Exploring the effect of exercise on telomere length and telomere-related proteins. BIOMED RESEARCH INTERNATIONAL 2013; 2013:601368. [PMID: 24455708 PMCID: PMC3884693 DOI: 10.1155/2013/601368] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Accepted: 11/26/2013] [Indexed: 01/29/2023]
Abstract
Aging is associated with a tissue degeneration phenotype marked by a loss of tissue regenerative capacity. Regenerative capacity is dictated by environmental and genetic factors that govern the balance between damage and repair. The age-associated changes in the ability of tissues to replace lost or damaged cells is partly the cause of many age-related diseases such as Alzheimer's disease, cardiovascular disease, type II diabetes, and sarcopenia. A well-established marker of the aging process is the length of the protective cap at the ends of chromosomes, called telomeres. Telomeres shorten with each cell division and with increasing chronological age and short telomeres have been associated with a range of age-related diseases. Several studies have shown that chronic exposure to exercise (i.e., exercise training) is associated with telomere length maintenance; however, recent evidence points out several controversial issues concerning tissue-specific telomere length responses. The goals of the review are to familiarize the reader with the current telomere dogma, review the literature exploring the interactions of exercise with telomere phenotypes, discuss the mechanistic research relating telomere dynamics to exercise stimuli, and finally propose future directions for work related to telomeres and physiological stress.
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30
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Hardeland R. Melatonin and the theories of aging: a critical appraisal of melatonin's role in antiaging mechanisms. J Pineal Res 2013; 55:325-56. [PMID: 24112071 DOI: 10.1111/jpi.12090] [Citation(s) in RCA: 192] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 08/23/2013] [Indexed: 02/06/2023]
Abstract
The classic theories of aging such as the free radical theory, including its mitochondria-related versions, have largely focused on a few specific processes of senescence. Meanwhile, numerous interconnections have become apparent between age-dependent changes previously thought to proceed more or less independently. Increased damage by free radicals is not only linked to impairments of mitochondrial function, but also to inflammaging as it occurs during immune remodeling and by release of proinflammatory cytokines from mitotically arrested, DNA-damaged cells that exhibit the senescence-associated secretory phenotype (SASP). Among other effects, SASP can cause mutations in stem cells that reduce the capacity for tissue regeneration or, in worst case, lead to cancer stem cells. Oxidative stress has also been shown to promote telomere attrition. Moreover, damage by free radicals is connected to impaired circadian rhythmicity. Another nexus exists between cellular oscillators and metabolic sensing, in particular to the aging-suppressor SIRT1, which acts as an accessory clock protein. Melatonin, being a highly pleiotropic regulator molecule, interacts directly or indirectly with all the processes mentioned. These influences are critically reviewed, with emphasis on data from aged organisms and senescence-accelerated animals. The sometimes-controversial findings obtained either in a nongerontological context or in comparisons of tumor with nontumor cells are discussed in light of evidence obtained in senescent organisms. Although, in mammals, lifetime extension by melatonin has been rarely documented in a fully conclusive way, a support of healthy aging has been observed in rodents and is highly likely in humans.
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Affiliation(s)
- Rüdiger Hardeland
- Johann Friedrich Blumenbach Institute of Zoology and Anthropology, University of Göttingen, Göttingen, Germany
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31
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Yan Y, Tan J, Ou T, Huang Z, Gu L. DNA G-quadruplex binders: a patent review. Expert Opin Ther Pat 2013; 23:1495-509. [DOI: 10.1517/13543776.2013.833187] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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32
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Lu H, Lei Z, Lu Z, Lu Q, Lu C, Chen W, Wang C, Tang Q, Kong Q. Silencing tankyrase and telomerase promotes A549 human lung adenocarcinoma cell apoptosis and inhibits proliferation. Oncol Rep 2013; 30:1745-52. [PMID: 23933993 DOI: 10.3892/or.2013.2665] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 07/30/2013] [Indexed: 11/05/2022] Open
Abstract
Telomeres are the end structures of chromosomes in mammalian cells; they play a pivotal role in maintaining the stability of the chromosome and become shorter with each cell division. However, several types of tumor cells express telomerase in very high levels to overcome this crisis and achieve the ability to proliferate endlessly. The telomerase inhibitors can partly inhibit tumor cell proliferation and promote apoptosis, but their roles are only limited. Tankyrase is a poly(ADP-ribose) polymerase which has synergistic effect on telomerase, and is expressed in lung cancer cells in high levels. In the present study, antisense oligonucleotides of telomerase (ashTERT) and tankyrase (asTANKS) were used as specific inhibitors to silence the expression of target genes in A549 human lung adenocarcinoma cells by transfection. The results showed that ashTERT and asTANKS suppressed the expression of telomerase and tankyrase significantly; both inhibited the activity of telomerase and the combination group achieved better effect, but only ashTERT shortened the length of telomeres, asTANKS did not. Further studies showed that ashTERT and asTANKS-promoted A549 apoptosis was not mediated by downregulation of the expression of the anti-apoptotic gene BCL-2 or upregulation of the expression of the pro-apoptotic gene BAX, but by adjusting the two isoforms proportion of myeloid cell leukemia-1 (MCL-1) which can interact with tankyrase directly. MCL-1short (MCL-1S), a pro-apoptotic gene, increased more than MCL-1Long (MCL-1L) which is an anti-apoptotic gene, leading to A549 cell apoptosis and a similar result was obtained in nude mice in vivo. The present study suggests that combination of the inhibitors of telomerase and tankyrase can be used as a strategy for the treatment of lung cancer in humans.
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Affiliation(s)
- Hongda Lu
- Department of Oncology, the Central Hospital of Wuhan, Wuhan, Hubei, P.R. China
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33
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Dorrington MG, Bowdish DME. Immunosenescence and novel vaccination strategies for the elderly. Front Immunol 2013; 4:171. [PMID: 23825474 PMCID: PMC3695377 DOI: 10.3389/fimmu.2013.00171] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 06/14/2013] [Indexed: 01/20/2023] Open
Abstract
Vaccination remains the most effective prophylactic intervention for infectious disease in the healthcare professional's toolkit. However, the efficacy and effectiveness of vaccines decrease with age. This becomes most apparent after an individual reaches 65-70 years old, and results from complex changes in the immune system that occur during aging. As such, new vaccine formulations and strategies that can accommodate age-related changes in immunity are required to protect this expanding population. Here, we summarize the consequences of immunosenescence on vaccination and how novel vaccination strategies can be designed to accommodate the aging immune system. We conclude that current vaccination protocols are not sufficient to protect our aging population and, in some cases, are an inefficient use of healthcare resources. However, researchers and clinicians are developing novel vaccination strategies that include modifying who and when we vaccinate and capitalize on existing vaccines, in addition to formulating new vaccines specifically tailored to the elderly in order to remedy this deficiency.
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Affiliation(s)
- Michael G. Dorrington
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
| | - Dawn M. E. Bowdish
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON L8S 4L8, Canada
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34
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Bidwell JP, Alvarez MB, Hood M, Childress P. Functional impairment of bone formation in the pathogenesis of osteoporosis: the bone marrow regenerative competence. Curr Osteoporos Rep 2013; 11:117-25. [PMID: 23471774 DOI: 10.1007/s11914-013-0139-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The skeleton is a high-renewal organ that undergoes ongoing cycles of remodeling. The regenerative bone formation arm ultimately declines in the aging, postmenopausal skeleton, but current therapies do not adequately address this deficit. Bone marrow is the primary source of the skeletal anabolic response and the mesenchymal stem cells (MSCs), which give rise to bone matrix-producing osteoblasts. The identity of these stem cells is emerging, but it now appears that the term 'MSC' has often been misapplied to the bone marrow stromal cell (BMSC), a progeny of the MSC. Nevertheless, the changes in BMSC phenotype associated with age and estrogen depletion likely contribute to the attenuated regenerative competence of the marrow and may reflect alterations in MSC phenotype. Here we summarize current concepts in bone marrow MSC identity, and within this context, review recent observations on changes in bone marrow population dynamics associated with aging and menopause.
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Affiliation(s)
- Joseph P Bidwell
- Department of Anatomy and Cell Biology, Indiana University School of Medicine (IUSM), Medical Science Bldg 5035, 635 Barnhill Drive, Indianapolis, IN 46202, USA.
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35
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Accumulation of DNA damage-induced chromatin alterations in tissue-specific stem cells: the driving force of aging? PLoS One 2013; 8:e63932. [PMID: 23691119 PMCID: PMC3656879 DOI: 10.1371/journal.pone.0063932] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 04/08/2013] [Indexed: 01/11/2023] Open
Abstract
Accumulation of DNA damage leading to stem cell exhaustion has been proposed to be a principal mechanism of aging. Using 53BP1-foci as a marker for DNA double-strand breaks (DSBs), hair follicle stem cells (HFSCs) in mouse epidermis were analyzed for age-related DNA damage response (DDR). We observed increasing amounts of 53BP1-foci during the natural aging process independent of telomere shortening and after protracted low-dose radiation, suggesting substantial accumulation of DSBs in HFSCs. Electron microscopy combined with immunogold-labeling showed multiple small 53BP1 clusters diffusely distributed throughout the highly compacted heterochromatin of aged HFSCs, but single large 53BP1 clusters in irradiated HFSCs. These remaining 53BP1 clusters did not colocalize with core components of non-homologous end-joining, but with heterochromatic histone modifications. Based on these results we hypothesize that these lesions were not persistently unrepaired DSBs, but may reflect chromatin rearrangements caused by the repair or misrepair of DSBs. Flow cytometry showed increased activation of repair proteins and damage-induced chromatin modifications, triggering apoptosis and cellular senescence in irradiated, but not in aged HFSCs. These results suggest that accumulation of DNA damage-induced chromatin alterations, whose structural dimensions reflect the complexity of the initial genotoxic insult, may lead to different DDR events, ultimately determining the biological outcome of HFSCs. Collectively, our findings support the hypothesis that aging might be largely the remit of structural changes to chromatin potentially leading to epigenetically induced transcriptional deregulation.
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36
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Jacobs JJL. Loss of telomere protection: consequences and opportunities. Front Oncol 2013; 3:88. [PMID: 23596571 PMCID: PMC3625723 DOI: 10.3389/fonc.2013.00088] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 04/02/2013] [Indexed: 01/22/2023] Open
Abstract
Telomeres are repetitive sequences at the natural ends of linear eukaryotic chromosomes that protect these from recognition as chromosome breaks. Their ability to do so critically depends on the binding of sufficient quantities of functional shelterin, a six-unit protein complex with specific and crucial roles in telomere maintenance and function. Insufficient telomere length, leading to insufficient concentration of shelterin at chromosome ends, or otherwise crippled shelterin function, causes telomere deprotection. While contributing to aging-related pathologies, loss of telomere protection can act as a barrier to tumorigenesis, as dysfunctional telomeres activate DNA-damage-like checkpoint responses that halt cell proliferation or trigger cell death. In addition, dysfunctional telomeres affect cancer development and progression by being a source of genomic instability. Reviewed here are the different approaches that are being undertaken to investigate the mammalian cellular response to telomere dysfunction and its consequences for cancer. Furthermore, it is discussed how current and future knowledge about the mechanisms underlying telomere damage responses might be applied for diagnostic purposes or therapeutic intervention.
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Affiliation(s)
- Jacqueline J L Jacobs
- Division of Molecular Oncology, The Netherlands Cancer Institute Amsterdam, Netherlands
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