1
|
Peng L, Dan J, Huang W, Sang L, Tian H, Li Z, Li W, Liu J, Luo Y. The dual effects of Congea chinensis Moldenke on inhibiting tumor cell proliferation and delaying aging by activating TERT transcriptional activity. JOURNAL OF ETHNOPHARMACOLOGY 2024; 319:117103. [PMID: 37673201 DOI: 10.1016/j.jep.2023.117103] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/21/2023] [Accepted: 08/28/2023] [Indexed: 09/08/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Natural medicinal plants, also named herbs, have attracted considerable research attention for their potential pharmacological activities, such as antitumor and longevity-promoting activities. Our previous review proposed that maintaining the homeostatic balance between aging and cancer may benefit organisms to enable tumor-free longevity. Congea chinensis Moldenke (CCM) is a plant species that grows on the border of Yunnan Province of China. Its medicinal value has been few reports until now. Thus, screening and extraction the ingredients from CCM that are both active tumor suppressors and TERT activators is a therapeutic strategy for improving tumor-free longevity. AIM OF THE STUDY To extract and evaluate the cytotoxic antitumor and TERT transcription-promoting activities of the plant CCM. MATERIALS AND METHODS The ingredients extracted from CCM were tested for transcriptional activation of p53 using pGL4-p53-GFP cells and for TERT expression using a real-time PCR assay. In vitro antitumor activity was detected by sulforhodamine B (SRB) assay and Annexin V/PI staining assay. The cell-permeable probe H2DCFDA was used to detect intracellular reactive oxygen species (ROS). Western blot was performed to verify predicated proteins regulated by the ingredients. RNA-sequence analysis was applied to predicate the underlying mechanism of CCM. RESULTS Both CCM and MPRC2-8, two novel extracts of Congea chinensis Moldenke, activated the expression of p53 and TERT and were selectively cytotoxic toward tumor cells. In addition, the cytotoxic mechanism of MPRC2-8 was identified as ROS generation-induced apoptosis. Interestingly, MPRC2-8 showed opposite regulatory effects on the SIRT1-p53 axis in A549 and HT-29 cells, which have different p53 statuses. RNA-seq analysis showed that CCM and MPRC2-8 induced the p53, apoptosis and ROS signaling pathways, consistent with the results of cellular experiments in vitro. CONCLUSION Our study reveals that CCM and MPRC2-8 have two complementary activities, antitumor activity and TERT-activating activity, with potential antitumor and longevity-improving effects.
Collapse
Affiliation(s)
- Lei Peng
- Laboratory of Molecular Genetics of Aging and Tumor, Medical School, Kunming University of Science and Technology, Kunming, 650500, China
| | - Juhua Dan
- Laboratory of Molecular Genetics of Aging and Tumor, Medical School, Kunming University of Science and Technology, Kunming, 650500, China
| | - Wenhui Huang
- Laboratory of Molecular Genetics of Aging and Tumor, Medical School, Kunming University of Science and Technology, Kunming, 650500, China
| | - Lei Sang
- Laboratory of Molecular Genetics of Aging and Tumor, Medical School, Kunming University of Science and Technology, Kunming, 650500, China
| | - Hao Tian
- Institute of Medicinal Plants, Yunnan Academy of Agricultural Sciences, Kunming, 650200, China
| | - Zhiming Li
- Institute of Medicinal Plants, Yunnan Academy of Agricultural Sciences, Kunming, 650200, China
| | - Wanyi Li
- Institute of Medicinal Plants, Yunnan Academy of Agricultural Sciences, Kunming, 650200, China.
| | - Jing Liu
- Laboratory of Molecular Genetics of Aging and Tumor, Medical School, Kunming University of Science and Technology, Kunming, 650500, China.
| | - Ying Luo
- Guizhou Provincial Key Laboratory of Pathogenesis & Drug Development on Common Chronic Diseases, School of Basic Medicine, Guizhou Medical University, Guiyang, China.
| |
Collapse
|
2
|
Orabi MAA, Abdelhamid RA, Elimam H, Elshaier YAMM, Ali AA, Aldabaan N, Alhasaniah AH, Refaey MS. Furofuranoid-Type Lignans and Related Phenolics from Anisacanthus virgularis (Salisb.) Nees with Promising Anticholinesterase and Anti-Ageing Properties: A Study Supported by Molecular Modelling. PLANTS (BASEL, SWITZERLAND) 2024; 13:150. [PMID: 38256704 PMCID: PMC10820861 DOI: 10.3390/plants13020150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Revised: 12/23/2023] [Accepted: 01/03/2024] [Indexed: 01/24/2024]
Abstract
Lignan phytomolecules demonstrate promising anti-Alzheimer activity by alleviating dementia and preserving nerve cells. The purpose of this work is to characterize the lignans of Anisacanthus virgularis and explore their potential anti-acetylcholinesterase and anti-ageing effects. Phytochemical investigation of A. virgularis aerial parts afforded a new furofuranoid-type lignan (1), four known structural analogues, namely pinoresinol (2), epipinoresinol (3), phillyrin (4), and pinoresinol 4-O-β-d-glucoside (5), in addition to p-methoxy-trans-methyl cinnamate (6) and 1H-indole-3-carboxaldehyde (7). The structures were established from thorough spectroscopic analyses and comparisons with the literature. Assessment of the anticholinesterase activity of the lignans 1-5 displayed noticeable enzyme inhibition of 1 (IC50 = 85.03 ± 4.26 nM) and 5 (64.47 ± 2.75 nM) but lower activity of compounds 2-4 as compared to the reference drug donepezil. These findings were further emphasized by molecular docking of 1 and 5 with acetylcholinesterase (AChE). Rapid overlay chemical similarity (ROCS) and structure-activity relationships (SAR) analysis highlighted and rationalized the anti-AD capability of these compounds. Telomerase activation testing of the same isolates revealed 1.64-, 1.66-, and 1.72-fold activations in cells treated with compounds 1, 5, and 4, respectively, compared to untreated cells. Our findings may pave the way for further investigations into the development of anti-Alzheimer and/or anti-ageing drugs from furofuranoid-type lignans.
Collapse
Affiliation(s)
- Mohamed A. A. Orabi
- Department of Pharmacognosy, College of Pharmacy, Najran University, Najran 66454, Saudi Arabia
| | - Reda A. Abdelhamid
- Department of Pharmacognosy, Faculty of Pharmacy, Al-Azhar University, Assiut-Branch, Assiut 71524, Egypt;
| | - Hanan Elimam
- Department of Biochemistry, Faculty of Pharmacy, University of Sadat City, Sadat City 32958, Egypt;
| | - Yaseen A. M. M. Elshaier
- Department of Organic and Medicinal Chemistry, Faculty of Pharmacy, University of Sadat City, Sadat City 32958, Egypt;
| | - Ahmed A. Ali
- Department of Pharmacognosy, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt;
| | - Nayef Aldabaan
- Department of Pharmacology, College of Pharmacy, Najran University, Najran 66454, Saudi Arabia;
| | - Abdulaziz Hassan Alhasaniah
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Najran University, Najran 66454, Saudi Arabia;
| | - Mohamed S. Refaey
- Department of Pharmacognosy, Faculty of Pharmacy, University of Sadat City, Sadat City 32958, Egypt
| |
Collapse
|
3
|
Musa I, Yang N, Breslin J, Paulden O, Geliebter J, Tiwari R, Li XM. Inhibition of Myeloma Cell Function by Cannabinoid-Enriched Product Associated With Regulation of Telomere and TP53. Integr Cancer Ther 2024; 23:15347354241267979. [PMID: 39256983 PMCID: PMC11406604 DOI: 10.1177/15347354241267979] [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] [Indexed: 09/12/2024] Open
Abstract
Multiple myeloma is a hematological cancer caused by the uncontrolled proliferation of abnormal plasma cells in the bone marrow, leading to excessive immunoglobulin production. Our study aimed to examine the anticancer properties of BRF1A, a cannabinoid (CBD)-enriched product, on 2 myeloma cell lines: U266 and ARH-7. We treated U266 and ARH-77 myeloma cells with varying doses of BRF1A and measured the production of IgE and IgG antibodies using ELISA. Cell viability was assessed using trypan blue and CCK-8 assays. We measured the expression of genes related to the production of IgE and IgG antibodies, IgEH, and IgGH. We determined its effect on the expression of telomerase and its phosphorylated form as an indicator of telomere stabilization. Furthermore, we determined its effect on other cancer-related targets such as NF-ĸB, c-Myc, and TP53 in U266 cells using reverse transcription polymerase chain reaction (RT-PCR) and western blotting. BRF1A reduced myeloma cell IgE and IgG production in a time and dose-dependent manner. It also suppressed the expression of p-IκBα, p-NFκB (p65), and total NFκB protein, as well as XBP1u and XBP1s. It increased the gene and protein expression of telomere and hTERT and significantly increased cancer suppressor TP53 gene and p53 protein expression. Additionally, BRF1A decreased the c-Myc gene and protein expression. Our study has shown that a CBD-enriched product can reduce the growth of myeloma cells by suppressing the critical functions of IgE- and IgG-producing cells. This study could help bridge the gap in understanding how cannabinoid-containing products affect cancer, aging, telomere, and cancer-suppressor gene activity.
Collapse
Affiliation(s)
| | - Nan Yang
- General Nutraceutical Technology LLC, Elmsford, NY, USA
| | | | | | | | - Raj Tiwari
- New York Medical College, Valhalla, NY, USA
| | - Xiu-Min Li
- New York Medical College, Valhalla, NY, USA
| |
Collapse
|
4
|
Landa I, Thornton CE, Xu B, Haase J, Krishnamoorthy GP, Hao J, Knauf JA, Herbert ZT, Martínez P, Blasco MA, Ghossein R, Fagin JA. Telomerase Upregulation Induces Progression of Mouse BrafV600E-Driven Thyroid Cancers and Triggers Nontelomeric Effects. Mol Cancer Res 2023; 21:1163-1175. [PMID: 37478162 PMCID: PMC11193891 DOI: 10.1158/1541-7786.mcr-23-0144] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 06/15/2023] [Accepted: 07/18/2023] [Indexed: 07/23/2023]
Abstract
Mutations in the promoter of the telomerase reverse transcriptase (TERT) gene are the paradigm of a cross-cancer alteration in a noncoding region. TERT promoter mutations (TPM) are biomarkers of poor prognosis in cancer, including thyroid tumors. TPMs enhance TERT transcription, which is otherwise silenced in adult tissues, thus reactivating a bona fide oncoprotein. To study TERT deregulation and its downstream consequences, we generated a Tert mutant promoter mouse model via CRISPR/Cas9 engineering of the murine equivalent locus (Tert-123C>T) and crossed it with thyroid-specific BrafV600E-mutant mice. We also employed an alternative model of Tert overexpression (K5-Tert). Whereas all BrafV600E animals developed well-differentiated papillary thyroid tumors, 29% and 36% of BrafV600E+Tert-123C>T and BrafV600E+K5-Tert mice progressed to poorly differentiated cancers at week 20, respectively. Tert-upregulated tumors showed increased mitosis and necrosis in areas of solid growth, and older animals displayed anaplastic-like features, that is, spindle cells and macrophage infiltration. Murine TPM increased Tert transcription in vitro and in vivo, but temporal and intratumoral heterogeneity was observed. RNA-sequencing of thyroid tumor cells showed that processes other than the canonical Tert-mediated telomere maintenance role operate in these specimens. Pathway analysis showed that MAPK and PI3K/AKT signaling, as well as processes not previously associated with this tumor etiology, involving cytokine, and chemokine signaling, were overactivated. These models constitute useful preclinical tools to understand the cell-autonomous and microenvironment-related consequences of Tert-mediated progression in advanced thyroid cancers and other aggressive tumors carrying TPMs. IMPLICATIONS Telomerase-driven cancer progression activates pathways that can be dissected and perhaps therapeutically exploited.
Collapse
Affiliation(s)
- Iñigo Landa
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | - Caitlin E.M. Thornton
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | - Bin Xu
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Jacob Haase
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | - Gnana P. Krishnamoorthy
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Jingzhu Hao
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | | | - Zachary T. Herbert
- Molecular Biology Core Facilities, Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Paula Martínez
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain
| | - María A. Blasco
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain
| | - Ronald Ghossein
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - James A. Fagin
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| |
Collapse
|
5
|
Holloway K, Neherin K, Dam KU, Zhang H. Cellular senescence and neurodegeneration. Hum Genet 2023; 142:1247-1262. [PMID: 37115318 DOI: 10.1007/s00439-023-02565-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Accepted: 04/20/2023] [Indexed: 04/29/2023]
Abstract
Advancing age is a major risk factor of Alzheimer's disease (AD). The worldwide prevalence of AD is approximately 50 million people, and this number is projected to increase substantially. The molecular mechanisms underlying the aging-associated susceptibility to cognitive impairment in AD are largely unknown. As a hallmark of aging, cellular senescence is a significant contributor to aging and age-related diseases including AD. Senescent neurons and glial cells have been detected to accumulate in the brains of AD patients and mouse models. Importantly, selective elimination of senescent cells ameliorates amyloid beta and tau pathologies and improves cognition in AD mouse models, indicating a critical role of cellular senescence in AD pathogenesis. Nonetheless, the mechanisms underlying when and how cellular senescence contributes to AD pathogenesis remain unclear. This review provides an overview of cellular senescence and discusses recent advances in the understanding of the impact of cellular senescence on AD pathogenesis, with brief discussions of the possible role of cellular senescence in other neurodegenerative diseases including Down syndrome, Parkinson's disease, multiple sclerosis, and amyotrophic lateral sclerosis.
Collapse
Affiliation(s)
- Kristopher Holloway
- Department of Pediatrics, University of Massachusetts Chan Medical School, Worcester, MA, 01655, USA
| | - Kashfia Neherin
- Department of Pediatrics, University of Massachusetts Chan Medical School, Worcester, MA, 01655, USA
| | - Kha Uyen Dam
- Department of Pediatrics, University of Massachusetts Chan Medical School, Worcester, MA, 01655, USA
| | - Hong Zhang
- Department of Pediatrics, University of Massachusetts Chan Medical School, Worcester, MA, 01655, USA.
| |
Collapse
|
6
|
El Maï M, Bird M, Allouche A, Targen S, Şerifoğlu N, Lopes-Bastos B, Guigonis JM, Kang D, Pourcher T, Yue JX, Ferreira MG. Gut-specific telomerase expression counteracts systemic aging in telomerase-deficient zebrafish. NATURE AGING 2023; 3:567-584. [PMID: 37142828 DOI: 10.1038/s43587-023-00401-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 03/21/2023] [Indexed: 05/06/2023]
Abstract
Telomere shortening is a hallmark of aging and is counteracted by telomerase. As in humans, the zebrafish gut is one of the organs with the fastest rate of telomere decline, triggering early tissue dysfunction during normal zebrafish aging and in prematurely aged telomerase mutants. However, whether telomere-dependent aging of an individual organ, the gut, causes systemic aging is unknown. Here we show that tissue-specific telomerase expression in the gut can prevent telomere shortening and rescues premature aging of tert-/-. Induction of telomerase rescues gut senescence and low cell proliferation, while restoring tissue integrity, inflammation and age-dependent microbiota dysbiosis. Averting gut aging causes systemic beneficial impacts, rescuing aging of distant organs such as reproductive and hematopoietic systems. Conclusively, we show that gut-specific telomerase expression extends the lifespan of tert-/- by 40%, while ameliorating natural aging. Our work demonstrates that gut-specific rescue of telomerase expression leading to telomere elongation is sufficient to systemically counteract aging in zebrafish.
Collapse
Affiliation(s)
- Mounir El Maï
- Institute for Research on Cancer and Aging of Nice (IRCAN), CNRS UMR7284, INSERM U1081, Université Côte d'Azur, Nice, France
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Malia Bird
- Institute for Research on Cancer and Aging of Nice (IRCAN), CNRS UMR7284, INSERM U1081, Université Côte d'Azur, Nice, France
| | - Asma Allouche
- Institute for Research on Cancer and Aging of Nice (IRCAN), CNRS UMR7284, INSERM U1081, Université Côte d'Azur, Nice, France
| | - Seniye Targen
- Institute for Research on Cancer and Aging of Nice (IRCAN), CNRS UMR7284, INSERM U1081, Université Côte d'Azur, Nice, France
| | - Naz Şerifoğlu
- Institute for Research on Cancer and Aging of Nice (IRCAN), CNRS UMR7284, INSERM U1081, Université Côte d'Azur, Nice, France
| | - Bruno Lopes-Bastos
- Institute for Research on Cancer and Aging of Nice (IRCAN), CNRS UMR7284, INSERM U1081, Université Côte d'Azur, Nice, France
| | - Jean-Marie Guigonis
- Laboratory Transporter in Imaging and Radiotherapy in Oncology, Institut des Sciences du Vivant Frederic Joliot, Commissariat à l'Energie Atomique et aux Energies Alternatives, Université Côte d'Azur, Nice, France
| | - Da Kang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Thierry Pourcher
- Laboratory Transporter in Imaging and Radiotherapy in Oncology, Institut des Sciences du Vivant Frederic Joliot, Commissariat à l'Energie Atomique et aux Energies Alternatives, Université Côte d'Azur, Nice, France
| | - Jia-Xing Yue
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Miguel Godinho Ferreira
- Institute for Research on Cancer and Aging of Nice (IRCAN), CNRS UMR7284, INSERM U1081, Université Côte d'Azur, Nice, France.
- Instituto Gulbenkian de Ciência, Oeiras, Portugal.
| |
Collapse
|
7
|
Landa I, Thornton CEM, Xu B, Haase J, Krishnamoorthy GP, Hao J, Knauf JA, Herbert ZT, Blasco MA, Ghossein R, Fagin JA. Telomerase reactivation induces progression of mouse Braf V600E -driven thyroid cancers without telomere lengthening. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.24.525280. [PMID: 36747657 PMCID: PMC9900760 DOI: 10.1101/2023.01.24.525280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Mutations in the promoter of the telomerase reverse transcriptase ( TERT ) gene are the paradigm of a cross-cancer alteration in a non-coding region. TERT promoter mutations (TPMs) are biomarkers of poor prognosis in several tumors, including thyroid cancers. TPMs enhance TERT transcription, which is otherwise silenced in adult tissues, thus reactivating a bona fide oncoprotein. To study TERT deregulation and its downstream consequences, we generated a Tert mutant promoter mouse model via CRISPR/Cas9 engineering of the murine equivalent locus (Tert -123C>T ) and crossed it with thyroid-specific Braf V600E -mutant mice. We also employed an alternative model of Tert overexpression (K5-Tert). Whereas all Braf V600E animals developed well-differentiated papillary thyroid tumors, 29% and 36% of Braf V600E +Tert -123C>T and Braf V600E +K5-Tert mice progressed to poorly differentiated thyroid cancers at week 20, respectively. Braf+Tert tumors showed increased mitosis and necrosis in areas of solid growth, and older animals from these cohorts displayed anaplastic-like features, i.e., spindle cells and macrophage infiltration. Murine Tert promoter mutation increased Tert transcription in vitro and in vivo , but temporal and intra-tumoral heterogeneity was observed. RNA-sequencing of thyroid tumor cells showed that processes other than the canonical Tert-mediated telomere maintenance role operate in these specimens. Pathway analysis showed that MAPK and PI3K/AKT signaling, as well as processes not previously associated with this tumor etiology, involving cytokine and chemokine signaling, were overactivated. Braf+Tert animals remained responsive to MAPK pathway inhibitors. These models constitute useful pre-clinical tools to understand the cell-autonomous and microenvironment-related consequences of Tert-mediated progression in advanced thyroid cancers and other aggressive tumors carrying TPMs.
Collapse
Affiliation(s)
- Iñigo Landa
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Caitlin EM Thornton
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Bin Xu
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Jacob Haase
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Gnana P. Krishnamoorthy
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Jingzhu Hao
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women’s Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Jeffrey A Knauf
- Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Zachary T Herbert
- Molecular Biology Core Facilities, Dana-Farber Cancer Institute, Boston, MA, USA
| | - María A Blasco
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain
| | - Ronald Ghossein
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - James A Fagin
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| |
Collapse
|
8
|
Refaey MS, Abdelhamid RA, Elimam H, Elshaier YAMM, Ali AA, Orabi MAA. Bioactive constituents from Thunbergia erecta as potential anticholinesterase and anti-ageing agents: Experimental and in silico studies. Bioorg Chem 2021; 108:104643. [PMID: 33486370 DOI: 10.1016/j.bioorg.2021.104643] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 12/13/2020] [Accepted: 01/05/2021] [Indexed: 12/13/2022]
Abstract
Acetylcholinesterase (AChE) inhibitor and telomerase reverse transcriptase (TERT) potentiator phytochemicals are highly targeted as anti-Alzheimerꞌs disease and as an anti-ageing process. A phytochemical study of Thunbergia erecta aerial parts resulted in the isolation of ten compounds (1-10). Their structures were identified based on spectral data and comparison with literature values. The activity of our pure isolates on AChE and TERT enzymes by documented in vitro assay methods were evaluated. The results indicated that apigenin (2), vanillic acid (4), and acacetin-7-O-β-D-glucoside (7) exhibited potent inhibition of AChE (IC50 37.33, 30.80 and 49.57 ng/mL, respectively), compared to the standard drug donepezil (IC50 31.25 ng/mL). In the TERT enzyme assay, compound 7 triggered a 1.66‑fold increase in telomerase activity at the concentration of 2.85 ng/ml. This is the first study that demonstrates that compound 7 isolated from T. erecta can lead to such telomerase activity relative to control cells. Virtual screening studies including docking, rapid overlay chemical structure (ROCS), and calculated structure-property relationships (SPR) were implemented in this work. Molecular docking studies supported the binding of compounds 2, 4, and 7 through hydrogen bonds (HBs) formation to essential amino acid residues namely ARG:24 A, SER:347 A, LYS:51 A, PHE:346 A, and GLY:345 A of acetylcholinesterase. ROCS and SPR analyses realized compound 2 as a possible treatment of Alzheimer's disease and as a lead compound for drug development process through applying semisynthetic modifications.
Collapse
Affiliation(s)
- Mohamed S Refaey
- Department of Pharmacognosy, Faculty of Pharmacy, University of Sadat City, Sadat City, Menoufiya 32958, Egypt
| | - Reda A Abdelhamid
- Department of Pharmacognosy, Faculty of Pharmacy, Al-Azhar University, Assiut Branch, Assiut 71524, Egypt
| | - Hanan Elimam
- Department of Biochemistry, Faculty of Pharmacy, University of Sadat City, Sadat City 32958, Egypt; Department of Medicine, McGill University Health Centre, National Research Institute, McGill University, Montreal, Quebec, Canada
| | - Yaseen A M M Elshaier
- Department of Organic and Medicinal chemistry, Faculty of Pharmacy, University of Sadat City, Sadat City, Menoufiya 32958, Egypt
| | - A A Ali
- Department of Pharmacognosy, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt
| | - Mohamed A A Orabi
- Department of Pharmacognosy, Faculty of Pharmacy, Al-Azhar University, Assiut Branch, Assiut 71524, Egypt.
| |
Collapse
|
9
|
Kamal S, Junaid M, Ejaz A, Bibi I, Akash MSH, Rehman K. The secrets of telomerase: Retrospective analysis and future prospects. Life Sci 2020; 257:118115. [PMID: 32698073 DOI: 10.1016/j.lfs.2020.118115] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 07/06/2020] [Accepted: 07/13/2020] [Indexed: 12/12/2022]
Abstract
Telomerase plays a significant role to maintain and regulate the telomere length, cellular immortality and senescence by the addition of guanine-rich repetitive sequences. Chronic inflammation or oxidative stress-induced infection downregulates TERT gene modifying telomerase activity thus contributing to the early steps of gastric carcinogenesis process. Furthermore, telomere-telomerase system performs fundamental role in the pathogenesis and progression of diabetes mellitus as well as in its vascular intricacy. The cessation of cell proliferation in cultured cells by inhibiting the telomerase activity of transformed cells renders the rationale for culling of telomerase as a target therapy for the treatment of metabolic disorders and various types of cancers. In this article, we have briefly described the role of immune system and malignant cells in the expression of telomerase with critical analysis on the gaps and potential for future studies. The key findings regarding the secrets of the telomerase summarized in this article will help in future treatment modalities for the prevention of various types of cancers and metabolic disorders notably diabetes mellitus.
Collapse
Affiliation(s)
- Shagufta Kamal
- Department of Biochemistry, Government College University Faisalabad, Pakistan
| | - Muhammad Junaid
- Department of Biochemistry, Government College University Faisalabad, Pakistan
| | - Arslan Ejaz
- Department of Biochemistry, Government College University Faisalabad, Pakistan
| | - Ismat Bibi
- Department of Chemistry, Islamia University, Bahawalpur, Pakistan
| | | | - Kanwal Rehman
- Department of Pharmacy, University of Agriculture, Faisalabad, Pakistan.
| |
Collapse
|
10
|
Stabilization of telomere by the antioxidant property of polyphenols: Anti-aging potential. Life Sci 2020; 259:118341. [PMID: 32853653 DOI: 10.1016/j.lfs.2020.118341] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 08/19/2020] [Accepted: 08/22/2020] [Indexed: 12/28/2022]
Abstract
Aging is a form of a gradual loss of physiological integrity that results in impaired cellular function and ultimately increased vulnerability to disease and death. This process is a significant risk factor for critical age-related disorders such as cancer, diabetes, cardiovascular disease, and neurological conditions. Several mechanisms contribute to aging, most notably progressive telomeres shortening, which can be counteracted by telomerase enzyme activity and increasing in this enzyme activity associated with partly delaying the onset of aging. Individual behaviors and environmental factors such as nutrition affect the life-span by impact the telomerase activity rate. Healthy eating habits, including antioxidant intakes, such as polyphenols, can have a positive effect on telomere length by this mechanism. In this review, after studying the underlying mechanisms of aging and understanding the relationships between telomeres, telomerase, and aging, it has been attempted to explain the effect of polyphenols on reversing the oxidative stress and aging process.
Collapse
|
11
|
Bonafè M, Sabbatinelli J, Olivieri F. Exploiting the telomere machinery to put the brakes on inflamm-aging. Ageing Res Rev 2020; 59:101027. [PMID: 32068123 DOI: 10.1016/j.arr.2020.101027] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 01/04/2020] [Accepted: 02/13/2020] [Indexed: 12/15/2022]
Abstract
Telomere shortening accompanies mammalian aging in vivo, and the burden of senescent cells with short telomeres and a senescence-associated secretory phenotype (SASP) increases with aging. The release into the cytoplasm and the extracellular vesicle-mediated intercellular exchange of telomeric TTAGGG repeats could exert an anti-inflammatory activity by preventing the activation of the misplaced nucleic acid-sensing pathway. Many pharmacological and genetic strategies have been developed to prevent telomere shortening or to achieve telomere elongation. Recently, it was demonstrated that telomere elongation can be obtained - without genetic manipulation - by culturing mice embryonic stem cells into appropriate media. Based on this observation, we hypothesize that environmental factors could affect the initial length of telomeres by modulating the activity of telomerase during the early stages of pregnancy. Therefore, organisms with longer telomeres could exploit the anti-inflammatory activity of telomeric sequences over an extended time span, eventually delaying the development and progression of age-related diseases.
Collapse
Affiliation(s)
- Massimiliano Bonafè
- Department of Experimental, Diagnostic and Specialty Medicine, AlmaMater Studiorum, Università di Bologna, Bologna, Italy
| | - Jacopo Sabbatinelli
- Department of Clinical and Molecular Sciences, Università Politecnica delle Marche, Ancona, Italy.
| | - Fabiola Olivieri
- Department of Clinical and Molecular Sciences, Università Politecnica delle Marche, Ancona, Italy; Center of Clinical Pathology and Innovative Therapy, IRCCS INRCA, Ancona, Italy
| |
Collapse
|
12
|
Nemirovich-Danchenko NM, Khodanovich MY. Telomerase Gene Editing in the Neural Stem Cells in vivo as a Possible New Approach against Brain Aging. RUSS J GENET+ 2020. [DOI: 10.1134/s1022795420040092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
13
|
Zheng Q, Huang J, Wang G. Mitochondria, Telomeres and Telomerase Subunits. Front Cell Dev Biol 2019; 7:274. [PMID: 31781563 PMCID: PMC6851022 DOI: 10.3389/fcell.2019.00274] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 10/24/2019] [Indexed: 12/11/2022] Open
Abstract
Mitochondrial functions and telomere functions have mostly been studied independently. In recent years, it, however, has become clear that there are intimate links between mitochondria, telomeres, and telomerase subunits. Mitochondrial dysfunctions cause telomere attrition, while telomere damage leads to reprogramming of mitochondrial biosynthesis and mitochondrial dysfunctions, which has important implications in aging and diseases. In addition, evidence has accumulated that telomere-independent functions of telomerase also exist and that the protein component of telomerase TERT shuttles between the nucleus and mitochondria under oxidative stress. Our previously published data show that the RNA component of telomerase TERC is also imported into mitochondria, processed, and exported back to the cytosol. These data show a complex regulation network where telomeres, nuclear genome, and mitochondria are co-regulated by multi-localization and multi-function proteins and RNAs. This review summarizes the connections between mitochondria and telomeres, the mitochondrion-related functions of telomerase subunits, and how they play a role in crosstalk between mitochondria and the nucleus.
Collapse
Affiliation(s)
- Qian Zheng
- School of Life Sciences, Tsinghua University, Beijing, China
| | - Jinliang Huang
- School of Life Sciences, Tsinghua University, Beijing, China
| | - Geng Wang
- School of Life Sciences, Tsinghua University, Beijing, China.,School of Life Sciences, Xiamen University, Xiamen, China
| |
Collapse
|
14
|
Muñoz-Lorente MA, Cano-Martin AC, Blasco MA. Mice with hyper-long telomeres show less metabolic aging and longer lifespans. Nat Commun 2019; 10:4723. [PMID: 31624261 PMCID: PMC6797762 DOI: 10.1038/s41467-019-12664-x] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 09/19/2019] [Indexed: 12/16/2022] Open
Abstract
Short telomeres trigger age-related pathologies and shorter lifespans in mice and humans. In the past, we generated mouse embryonic (ES) cells with longer telomeres than normal (hyper-long telomeres) in the absence of genetic manipulations, which contributed to all mouse tissues. To address whether hyper-long telomeres have deleterious effects, we generated mice in which 100% of their cells are derived from hyper-long telomere ES cells. We observe that these mice have longer telomeres and less DNA damage with aging. Hyper-long telomere mice are lean and show low cholesterol and LDL levels, as well as improved glucose and insulin tolerance. Hyper-long telomere mice also have less incidence of cancer and an increased longevity. These findings demonstrate that longer telomeres than normal in a given species are not deleterious but instead, show beneficial effects.
Collapse
Affiliation(s)
- Miguel A Muñoz-Lorente
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Melchor Fernández Almagro 3, Madrid, 28029, Spain
| | - Alba C Cano-Martin
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Melchor Fernández Almagro 3, Madrid, 28029, Spain
| | - Maria A Blasco
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Melchor Fernández Almagro 3, Madrid, 28029, Spain.
| |
Collapse
|
15
|
Grote C, Reinhardt D, Zhang M, Wang J. Regulatory mechanisms and clinical manifestations of musculoskeletal aging. J Orthop Res 2019; 37:1475-1488. [PMID: 30919498 PMCID: PMC9202363 DOI: 10.1002/jor.24292] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 03/13/2019] [Indexed: 02/04/2023]
Abstract
Aging is the strongest risk factor for degenerative bone and joint diseases. Clinical therapies for age-related musculoskeletal disorders face significant challenges as their pathogenic mechanisms remain largely unclear. This review article focuses on the recent advances in the understanding of regulatory mechanisms of musculoskeletal aging and their clinical relevance. We begin with the prevalence and socioeconomic impacts of major age-related musculoskeletal disorders such as sarcopenia, osteoporosis, osteoarthritis, and degenerative tendinopathy. The current understanding of responsible biological mechanisms involved in general aging is then summarized. Proposed molecular, cellular, and biomechanical mechanisms relevant to the clinical manifestations of aging in the musculoskeletal system are discussed in detail, with a focus on the disorders affecting muscle, bone, articular cartilage, and tendon. Although musculoskeletal aging processes share many common pathways with the aging of other body systems, unique molecular and cellular mechanisms may be involved in the aging processes of musculoskeletal tissues. Advancements in the understanding of regulatory mechanisms of musculoskeletal aging may promote the development of novel treatments for age-related musculoskeletal disorders. Finally, future research directions for major musculoskeletal tissues including functional interaction between the tissues and their clinical relevance to age-related musculoskeletal disorders are highlighted in the Future Prospects section. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1475-1488, 2019.
Collapse
Affiliation(s)
- Caleb Grote
- Harrington Laboratory for Molecular Orthopedics, Department of Orthopedic Surgery, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Daniel Reinhardt
- Harrington Laboratory for Molecular Orthopedics, Department of Orthopedic Surgery, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Mingcai Zhang
- Harrington Laboratory for Molecular Orthopedics, Department of Orthopedic Surgery, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Jinxi Wang
- Harrington Laboratory for Molecular Orthopedics, Department of Orthopedic Surgery, University of Kansas Medical Center, Kansas City, Kansas, USA
- Department of Biochemistry & Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas, USA
| |
Collapse
|
16
|
Hao J, Xie W, Li H, Li R. Prostate Cancer-Specific of DD3-driven Oncolytic Virus-harboring mK5 Gene. Open Med (Wars) 2018; 14:1-9. [PMID: 30613790 PMCID: PMC6310915 DOI: 10.1515/med-2019-0001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 05/29/2018] [Indexed: 12/24/2022] Open
Abstract
Prostate cancer (PCa) is the second most diagnosed cancer in Western male population. In this study, we insert mK5 (the mutational kringle5 of human plasminogen) into a DD3-promoted (differential display code 3) oncolytic adenovirus to construct OncoAd.mK5.DD3. E1A.dE1B, briefly, OAd.DD3.mK5. DD3 is one of the most prostate cancer specific promoters which can transcriptionally control adenoviral replication. mK5 has been proved to be able to inhibit the tumor angiogenesis and inhibit cell proliferation. Our results suggested that targeting PCa with OAd.DD3.mK5 elicited strong antitumor effect.
Collapse
Affiliation(s)
- Jiali Hao
- Xinyuan Institute of Medicine and Biotechnology, Zhejiang SciTech University, Hangzhou 310018, China
| | - Wenjie Xie
- Xinyuan Institute of Medicine and Biotechnology, Zhejiang SciTech University, Hangzhou 310018, China
| | - Hui Li
- Shanghai Yuansong biotechnology Co., Ltd., Shanghai, China
| | - Runsheng Li
- Key Laboratory of Contraceptive Drugs and Devices of NPFPC, Shanghai Institute of Planned Parenthood Research, Shanghai, China
| |
Collapse
|
17
|
Zhang S, Duan E. Fighting against Skin Aging: The Way from Bench to Bedside. Cell Transplant 2018; 27:729-738. [PMID: 29692196 PMCID: PMC6047276 DOI: 10.1177/0963689717725755] [Citation(s) in RCA: 335] [Impact Index Per Article: 55.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 07/05/2017] [Accepted: 07/14/2017] [Indexed: 12/31/2022] Open
Abstract
As the most voluminous organ of the body that is exposed to the outer environment, the skin suffers from both intrinsic and extrinsic aging factors. Skin aging is characterized by features such as wrinkling, loss of elasticity, laxity, and rough-textured appearance. This aging process is accompanied with phenotypic changes in cutaneous cells as well as structural and functional changes in extracellular matrix components such as collagens and elastin. In this review, we summarize these changes in skin aging, research advances of the molecular mechanisms leading to these changes, and the treatment strategies aimed at preventing or reversing skin aging.
Collapse
Affiliation(s)
- Shoubing Zhang
- Department of Histology and Embryology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui, China
- Central laboratory of Molecular and Cellular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui, China
| | - Enkui Duan
- State Key Lab of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
18
|
Yanai H, Budovsky A, Tacutu R, Barzilay T, Abramovich A, Ziesche R, Fraifeld VE. Tissue repair genes: the TiRe database and its implication for skin wound healing. Oncotarget 2018; 7:21145-55. [PMID: 27049721 PMCID: PMC5008274 DOI: 10.18632/oncotarget.8501] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 03/18/2016] [Indexed: 12/20/2022] Open
Abstract
Wound healing is an inherent feature of any multicellular organism and recent years have brought about a huge amount of data regarding regular and abnormal tissue repair. Despite the accumulated knowledge, modulation of wound healing is still a major biomedical challenge, especially in advanced ages. In order to collect and systematically organize what we know about the key players in wound healing, we created the TiRe (Tissue Repair) database, an online collection of genes and proteins that were shown to directly affect skin wound healing. To date, TiRe contains 397 entries for four organisms: Mus musculus, Rattus norvegicus, Sus domesticus, and Homo sapiens. Analysis of the TiRe dataset of skin wound healing-associated genes showed that skin wound healing genes are (i) over-conserved among vertebrates, but are under-conserved in invertebrates; (ii) enriched in extracellular and immuno-inflammatory genes; and display (iii) high interconnectivity and connectivity to other proteins. The latter may provide potential therapeutic targets. In addition, a slower or faster skin wound healing is indicative of an aging or longevity phenotype only when assessed in advanced ages, but not in the young. In the long run, we aim for TiRe to be a one-station resource that provides researchers and clinicians with the essential data needed for a better understanding of the mechanisms of wound healing, designing new experiments, and the development of new therapeutic strategies. TiRe is freely available online at http://www.tiredb.org.
Collapse
Affiliation(s)
- Hagai Yanai
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Center for Multidisciplinary Research on Aging, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Arie Budovsky
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Center for Multidisciplinary Research on Aging, Ben-Gurion University of the Negev, Beer Sheva, Israel.,Judea Regional Research & Development Center, Carmel, Israel
| | - Robi Tacutu
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Center for Multidisciplinary Research on Aging, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Thomer Barzilay
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Center for Multidisciplinary Research on Aging, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Amir Abramovich
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Center for Multidisciplinary Research on Aging, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Rolf Ziesche
- Division of Pulmonary Medicine, Department of Internal Medicine II, Medical University of Vienna, Waehringer Guertel, Vienna, Austria
| | - Vadim E Fraifeld
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Center for Multidisciplinary Research on Aging, Ben-Gurion University of the Negev, Beer Sheva, Israel
| |
Collapse
|
19
|
Schosserer M, Grillari J, Breitenbach M. The Dual Role of Cellular Senescence in Developing Tumors and Their Response to Cancer Therapy. Front Oncol 2017; 7:278. [PMID: 29218300 PMCID: PMC5703792 DOI: 10.3389/fonc.2017.00278] [Citation(s) in RCA: 174] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 11/06/2017] [Indexed: 12/11/2022] Open
Abstract
Cellular senescence describes an irreversible growth arrest characterized by distinct morphology, gene expression pattern, and secretory phenotype. The final or intermediate stages of senescence can be reached by different genetic mechanisms and in answer to different external and internal stresses. It has been maintained in the literature but never proven by clearcut experiments that the induction of senescence serves the evolutionary purpose of protecting the individual from development and growth of cancers. This hypothesis was recently scrutinized by new experiments and found to be partly true, but part of the gene activities now known to happen in senescence are also needed for cancer growth, leading to the view that senescence is a double-edged sword in cancer development. In current cancer therapy, cellular senescence is, on the one hand, intended to occur in tumor cells, as thereby the therapeutic outcome is improved, but might, on the other hand, also be induced unintentionally in non-tumor cells, causing inflammation, secondary tumors, and cancer relapse. Importantly, organismic aging leads to accumulation of senescent cells in tissues and organs of aged individuals. Senescent cells can occur transiently, e.g., during embryogenesis or during wound healing, with beneficial effects on tissue homeostasis and regeneration or accumulate chronically in tissues, which detrimentally affects the microenvironment by de- or transdifferentiation of senescent cells and their neighboring stromal cells, loss of tissue specific functionality, and induction of the senescence-associated secretory phenotype, an increased secretory profile consisting of pro-inflammatory and tissue remodeling factors. These factors shape their surroundings toward a pro-carcinogenic microenvironment, which fuels the development of aging-associated cancers together with the accumulation of mutations over time. We are presenting an overview of well-documented stress situations and signals, which induce senescence. Among them, oncogene-induced senescence and stress-induced premature senescence are prominent. New findings about the role of senescence in tumor biology are critically reviewed with respect to new suggestions for cancer therapy leveraging genetic and pharmacological methods to prevent senescence or to selectively kill senescent cells in tumors.
Collapse
Affiliation(s)
- Markus Schosserer
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Johannes Grillari
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Austrian Cluster for Tissue Regeneration, Vienna, Austria.,Christian Doppler Laboratory for Biotechnology of Skin Aging, Vienna, Austria.,Evercyte GmbH, Vienna, Austria
| | - Michael Breitenbach
- Department of Cell Biology, Division of Genetics, University of Salzburg, Salzburg, Austria
| |
Collapse
|
20
|
Rudenko TE, Bobkova IN, Kamyshova ES, Gorelova IA. [Role of the mechanisms of replicative cellular senescence in structural and functional changes of the vascular wall in chronic kidney disease]. TERAPEVT ARKH 2017; 89:102-109. [PMID: 28745697 DOI: 10.17116/terarkh2017896102-109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This review considers the mechanisms and risk factors for the development of replicative cellular senescence of the vascular wall in patients with CKD and discusses therapeutic approaches to slowing the accelerated vascular aging.
Collapse
Affiliation(s)
- T E Rudenko
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia, Moscow, Russia
| | - I N Bobkova
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia, Moscow, Russia
| | - E S Kamyshova
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia, Moscow, Russia
| | - I A Gorelova
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia, Moscow, Russia
| |
Collapse
|
21
|
Abstract
Telomeres are tandem repeat DNA sequences present at the ends of each eukaryotic chromosome to stabilize the genome structure integrity. Telomere lengths progressively shorten with each cell division. Inflammation and oxidative stress, which are implicated as major mechanisms underlying cardiovascular diseases, increase the rate of telomere shortening and lead to cellular senescence. In clinical studies, cardiovascular risk factors such as smoking, obesity, sedentary lifestyle, and hypertension have been associated with short leukocyte telomere length. In addition, low telomerase activity and short leukocyte telomere length have been observed in atherosclerotic plaque and associated with plaque instability, thus stroke or acute myocardial infarction. The aging myocardium with telomere shortening and accumulation of senescent cells limits the tissue regenerative capacity, contributing to systolic or diastolic heart failure. In addition, patients with ion-channel defects might have genetic imbalance caused by oxidative stress-related accelerated telomere shortening, which may subsequently cause sudden cardiac death. Telomere length can serve as a marker for the biological status of previous cell divisions and DNA damage with inflammation and oxidative stress. It can be integrated into current risk prediction and stratification models for cardiovascular diseases and can be used in precise personalized treatments. In this review, we summarize the current understanding of telomeres and telomerase in the aging process and their association with cardiovascular diseases. In addition, we discuss therapeutic interventions targeting the telomere system in cardiovascular disease treatments.
Collapse
|
22
|
Yeh JK, Wang CY. Telomeres and Telomerase in Cardiovascular Diseases. Genes (Basel) 2016; 7:genes7090058. [PMID: 27598203 PMCID: PMC5042389 DOI: 10.3390/genes7090058] [Citation(s) in RCA: 126] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Revised: 08/25/2016] [Accepted: 08/29/2016] [Indexed: 12/20/2022] Open
Abstract
Telomeres are tandem repeat DNA sequences present at the ends of each eukaryotic chromosome to stabilize the genome structure integrity. Telomere lengths progressively shorten with each cell division. Inflammation and oxidative stress, which are implicated as major mechanisms underlying cardiovascular diseases, increase the rate of telomere shortening and lead to cellular senescence. In clinical studies, cardiovascular risk factors such as smoking, obesity, sedentary lifestyle, and hypertension have been associated with short leukocyte telomere length. In addition, low telomerase activity and short leukocyte telomere length have been observed in atherosclerotic plaque and associated with plaque instability, thus stroke or acute myocardial infarction. The aging myocardium with telomere shortening and accumulation of senescent cells limits the tissue regenerative capacity, contributing to systolic or diastolic heart failure. In addition, patients with ion-channel defects might have genetic imbalance caused by oxidative stress-related accelerated telomere shortening, which may subsequently cause sudden cardiac death. Telomere length can serve as a marker for the biological status of previous cell divisions and DNA damage with inflammation and oxidative stress. It can be integrated into current risk prediction and stratification models for cardiovascular diseases and can be used in precise personalized treatments. In this review, we summarize the current understanding of telomeres and telomerase in the aging process and their association with cardiovascular diseases. In addition, we discuss therapeutic interventions targeting the telomere system in cardiovascular disease treatments.
Collapse
Affiliation(s)
- Jih-Kai Yeh
- Department of Cardiology, Chang Gung Memorial Hospital, 33305 Taoyuan, Taiwan.
| | - Chao-Yung Wang
- Department of Cardiology, Chang Gung Memorial Hospital, 33305 Taoyuan, Taiwan.
- Chang Gung University College of Medicine, 33302 Taoyuan, Taiwan.
| |
Collapse
|
23
|
Jäger K, Walter M. Therapeutic Targeting of Telomerase. Genes (Basel) 2016; 7:genes7070039. [PMID: 27455328 PMCID: PMC4962009 DOI: 10.3390/genes7070039] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Revised: 06/16/2016] [Accepted: 06/24/2016] [Indexed: 12/20/2022] Open
Abstract
Telomere length and cell function can be preserved by the human reverse transcriptase telomerase (hTERT), which synthesizes the new telomeric DNA from a RNA template, but is normally restricted to cells needing a high proliferative capacity, such as stem cells. Consequently, telomerase-based therapies to elongate short telomeres are developed, some of which have successfully reached the stage I in clinical trials. Telomerase is also permissive for tumorigenesis and 90% of all malignant tumors use telomerase to obtain immortality. Thus, reversal of telomerase upregulation in tumor cells is a potential strategy to treat cancer. Natural and small-molecule telomerase inhibitors, immunotherapeutic approaches, oligonucleotide inhibitors, and telomerase-directed gene therapy are useful treatment strategies. Telomerase is more widely expressed than any other tumor marker. The low expression in normal tissues, together with the longer telomeres in normal stem cells versus cancer cells, provides some degree of specificity with low risk of toxicity. However, long term telomerase inhibition may elicit negative effects in highly-proliferative cells which need telomerase for survival, and it may interfere with telomere-independent physiological functions. Moreover, only a few hTERT molecules are required to overcome senescence in cancer cells, and telomerase inhibition requires proliferating cells over a sufficient number of population doublings to induce tumor suppressive senescence. These limitations may explain the moderate success rates in many clinical studies. Despite extensive studies, only one vaccine and one telomerase antagonist are routinely used in clinical work. For complete eradication of all subpopulations of cancer cells a simultaneous targeting of several mechanisms will likely be needed. Possible technical improvements have been proposed including the development of more specific inhibitors, methods to increase the efficacy of vaccination methods, and personalized approaches. Telomerase activation and cell rejuvenation is successfully used in regenerative medicine for tissue engineering and reconstructive surgery. However, there are also a number of pitfalls in the treatment with telomerase activating procedures for the whole organism and for longer periods of time. Extended cell lifespan may accumulate rare genetic and epigenetic aberrations that can contribute to malignant transformation. Therefore, novel vector systems have been developed for a 'mild' integration of telomerase into the host genome and loss of the vector in rapidly-proliferating cells. It is currently unclear if this technique can also be used in human beings to treat chronic diseases, such as atherosclerosis.
Collapse
Affiliation(s)
- Kathrin Jäger
- Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, Berlin 13353, Germany.
| | - Michael Walter
- Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, Berlin 13353, Germany.
- Labor Berlin-Charité Vivantes Services GmbH, Sylter Str. 2, Berlin 13353, Germany.
| |
Collapse
|
24
|
Varela E, Muñoz-Lorente MA, Tejera AM, Ortega S, Blasco MA. Generation of mice with longer and better preserved telomeres in the absence of genetic manipulations. Nat Commun 2016; 7:11739. [PMID: 27252083 PMCID: PMC4895768 DOI: 10.1038/ncomms11739] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 04/26/2016] [Indexed: 12/17/2022] Open
Abstract
Although telomere length is genetically determined, mouse embryonic stem (ES) cells with telomeres of twice the normal size have been generated. Here, we use such ES cells with ‘hyper-long' telomeres, which also express green fluorescent protein (GFP), to generate chimaeric mice containing cells with both hyper-long and normal telomeres. We show that chimaeric mice contain GFP-positive cells in all mouse tissues, display normal tissue histology and normal survival. Both hyper-long and normal telomeres shorten with age, but GFP-positive cells retain longer telomeres as mice age. Chimaeric mice with hyper-long telomeres also accumulate fewer cells with short telomeres and less DNA damage with age, and express lower levels of p53. In highly renewing compartments, such as the blood, cells with hyper-long telomeres are longitudinally maintained or enriched with age. We further show that wound-healing rates in the skin are increased in chimaeric mice. Our work demonstrates that mice with functional, longer and better preserved telomeres can be generated without the need for genetic manipulations, such as TERT overexpression. Telomere shortening has been linked to some aspects of organismal ageing. Here the authors create chimaeric mice that contain a mix of cells with normal or unnaturally long telomeres, and show chimaeric mice are protected from some forms of ageing-associated cellular damage and have accelerated wound-healing.
Collapse
Affiliation(s)
- Elisa Varela
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, Madrid E-28029, Spain
| | - Miguel A Muñoz-Lorente
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, Madrid E-28029, Spain
| | - Agueda M Tejera
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, Madrid E-28029, Spain
| | - Sagrario Ortega
- Transgenics Mice Unit, Biotechnology Program, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, Madrid E-28029, Spain
| | - Maria A Blasco
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, Madrid E-28029, Spain
| |
Collapse
|
25
|
Solovyov IA, Dobrovol’skaya EV, Moskalev AA. Genetic control of circadian rhythms and aging. RUSS J GENET+ 2016. [DOI: 10.1134/s1022795416040104] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
26
|
Peng Y, Xuan M, Leung VYL, Cheng B. Stem cells and aberrant signaling of molecular systems in skin aging. Ageing Res Rev 2015; 19:8-21. [PMID: 25446806 DOI: 10.1016/j.arr.2014.10.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 10/24/2014] [Accepted: 10/30/2014] [Indexed: 02/07/2023]
Abstract
The skin is the body's largest organ and it is able to self-repair throughout an individual's life. With advanced age, skin is prone to degenerate in response to damage. Although cosmetic surgery has been widely adopted to rejuvinate skin, we are far from a clear understanding of the mechanisms responsible for skin aging. Recently, adult skin-resident stem/progenitor cells, growth arrest, senescence or apoptotic death and dysfunction caused by alterations in key signaling genes, such as Ras/Raf/MEK/ERK, PI3K/Akt-kinases, Wnt, p21 and p53, have been shown to play a vital role in skin regeneration. Simultaneously, enhanced telomere attrition, hormone exhaustion, oxidative stress, genetic events and ultraviolet radiation exposure that result in severe DNA damage, genomic instability and epigenetic mutations also contribute to skin aging. Therefore, cell replacement and targeting of the molecular systems found in skin hold great promise for controlling or even curing skin aging.
Collapse
Affiliation(s)
- Yan Peng
- Department of Orthopaedics & Traumatology, LKS Faculty of Medicine, The University of Hong Kong, L9-12, Lab block, Hong Kong, SAR, China; Department of Plastic Surgery, Guangzhou General Hospital of Guangzhou command, The Key Laboratory of Trauma Treatment & Tissue Repair of Tropical Area, PLA, GuangDong, 510010, PR China
| | - Min Xuan
- Southern Medical University, Guangzhou, 510010, PR China; Department of Plastic Surgery, Guangzhou General Hospital of Guangzhou command, The Key Laboratory of Trauma Treatment & Tissue Repair of Tropical Area, PLA, GuangDong, 510010, PR China
| | - Victor Y L Leung
- Department of Orthopaedics & Traumatology, LKS Faculty of Medicine, The University of Hong Kong, L9-12, Lab block, Hong Kong, SAR, China.
| | - Biao Cheng
- Southern Medical University, Guangzhou, 510010, PR China.
| |
Collapse
|
27
|
Brett JO, Rando TA. Alive and well? Exploring disease by studying lifespan. Curr Opin Genet Dev 2014; 26:33-40. [PMID: 25005743 DOI: 10.1016/j.gde.2014.05.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 05/10/2014] [Accepted: 05/26/2014] [Indexed: 12/11/2022]
Abstract
A common concept in aging research is that chronological age is the most important risk factor for the development of diverse diseases, including degenerative diseases and cancers. The mechanistic link between the aging process and disease pathogenesis, however, is still enigmatic. Nevertheless, measurement of lifespan, as a surrogate for biological aging, remains among the most frequently used assays in aging research. In this review, we examine the connection between 'normal aging' and age-related disease from the point of view that they form a continuum of aging phenotypes. This notion of common mechanisms gives rise to the converse postulate that diseases may be risk factors for accelerated aging. We explore the advantages and caveats associated with using lifespan as a metric to understand cell and tissue aging, focusing on the elucidation of molecular mechanisms and potential therapies for age-related diseases.
Collapse
Affiliation(s)
- Jamie O Brett
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA; Paul F. Glenn Laboratories for the Biology of Aging, Stanford University School of Medicine, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
| | - Thomas A Rando
- Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA; Paul F. Glenn Laboratories for the Biology of Aging, Stanford University School of Medicine, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA; Neurology Service and Rehabilitation Research and Development Center of Excellence, Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA.
| |
Collapse
|
28
|
Boccardi V, Paolisso G. Telomerase activation: a potential key modulator for human healthspan and longevity. Ageing Res Rev 2014; 15:1-5. [PMID: 24561251 DOI: 10.1016/j.arr.2013.12.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 12/18/2013] [Accepted: 12/23/2013] [Indexed: 12/12/2022]
Abstract
The elderly population is increasing progressively. Along with this increase the number of age related diseases, such as cardiovascular, neurodegenerative diseases, metabolic impairment and cancer, is also on the rise thereby negatively impacting the burden on health care systems. Telomere shortening and dysfunction results in cellular senescence, an irreversible proliferative arrest that has been suggested to promote organismal aging and disabling age-related diseases. Given that telomerase, the enzyme responsible for maintaining telomere lengths, is not expressed at levels sufficient to prevent telomere shortening in most of our cells, telomeres progressively erode with advancing age. Telomerase activation, therefore, might serve as a viable therapeutic strategy to delay the onset of cellular senescence, tissue dysfunction and organismal decline. Here we analyze the more recent findings in telomerase activation as a potential key modulator for human healthspan and longevity.
Collapse
|
29
|
Polymorphisms within the Telomerase Reverse Transcriptase gene (TERT) in four breeds of dogs selected for difference in lifespan and cancer susceptibility. BMC Vet Res 2014; 10:20. [PMID: 24423165 PMCID: PMC3904191 DOI: 10.1186/1746-6148-10-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Accepted: 01/07/2014] [Indexed: 01/11/2023] Open
Abstract
Background Enzymatic activity of Telomerase Reverse Transcriptase (TERT) is important in maintaining the telomere length and has been implicated in cancer and aging related pathology. Since cancer susceptibility as well as longevity of dogs vary between breeds, this study involved sequencing the entire TERT gene of Canis familiaris from DNA samples obtained from forty dogs, with ten dogs each of four breeds: Shih Tzu, Dachshund, Irish Wolfhound, and Newfoundland, each with different life expectancies and susceptibility to cancer. Results We compared the sequences of all forty individuals amongst one another and with the published sequence of canine TERT, and analyzed relationships between members of the same or different breeds. Two separate phylogenetic trees were generated and analyzed from these individuals. Polymorphisms were found most frequently in intronic regions of the gene, although exonic polymorphisms also were observed. In many locations genotypes were observed that were either homozygous for the reference sequence or heterozygous, but the variant homozygous genotype was not observed. Conclusions We propose that these homozygous variants are likely to have adverse effects in dogs. It was also found that the polymorphisms did not segregate by breed. Because the four breeds chosen come from geographically and physiologically distinct backgrounds, it can be inferred that the polymorphic diversification of TERT preceded breed derivation.
Collapse
|
30
|
|
31
|
Mitteldorf JJ. Telomere biology: Cancer firewall or aging clock? BIOCHEMISTRY (MOSCOW) 2013; 78:1054-60. [DOI: 10.1134/s0006297913090125] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
32
|
Bernardes de Jesus B, Blasco MA. Telomerase at the intersection of cancer and aging. Trends Genet 2013; 29:513-20. [PMID: 23876621 DOI: 10.1016/j.tig.2013.06.007] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 06/07/2013] [Accepted: 06/18/2013] [Indexed: 12/16/2022]
Abstract
Although cancer and aging have been studied as independent diseases, mounting evidence suggests that cancer is an aging-associated disease and that cancer and aging share many molecular pathways. In particular, recent studies validated telomerase activation as a potential therapeutic target for age-related diseases; in addition, abnormal telomerase expression and telomerase mutations have been associated with many different types of human tumor. Here, we revisit the connection between telomerase and cancer and aging in light of recent findings supporting a role for telomerase not only in telomere elongation, but also in metabolic fitness and Wnt activation. Understanding the physiological impact of telomerase regulation is fundamental given the therapeutic strategies that are being developed that involve telomerase modulation.
Collapse
Affiliation(s)
- Bruno Bernardes de Jesus
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, Madrid, E-28029, Spain
| | | |
Collapse
|
33
|
Li J, Cao X, Fang Y, Liao ZE, Liu YY, Huang BD, Han YJ. Overexpression of hTERT in potentially malignant colorectal laterally spreading tumors. Mol Med Rep 2013; 7:1409-12. [PMID: 23525166 DOI: 10.3892/mmr.2013.1376] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Accepted: 02/27/2013] [Indexed: 11/06/2022] Open
Abstract
Human telomerase reverse transcriptase (hTERT) is the main subunit of the core enzyme telomerase, which consists of three subunits. Telomeres are essential for chromosomal stability and integrity, protecting the ends of chromosomes from degradation and preventing chromosomal end fusions and recombination. A loss of telomere function is a major mechanism for the generation of chromosomal abnormalities. Telomere shortening leads to mutations, chromosome rearrangements and translocations. Colorectal laterally spreading tumors (LSTs) are a special type of superficial colorectal tumor. They are considered to have a high malignancy potential. The aim of the present study was to characterize the expression of hTERT in an LST cell line and paraffin sections. Immunohistochemistry was utilized to examine the protein expression of hTERT in the LST cell line, 48 resected LSTs, 48 protruded-type colorectal adenomas (PAs) and 48 normal mucosa samples. Statistical analyses were applied to test the associations between hTERT expression and clinicopathological parameters. The present study demonstrated that the positive expression levels of hTERT in LSTs, PAs and normal mucosa were 60.4, 22.9 and 10%, respectively. Compared with polypi and normal mucosa, the expression levels of hTERT were significantly increased in LSTs. The expression of hTERT was also observed in the LST cell line. The expression of hTERT was significantly higher in LSTs, which may indicate a potential for malignancy.
Collapse
Affiliation(s)
- Jun Li
- Department of Traditional Chinese Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, PR China
| | | | | | | | | | | | | |
Collapse
|
34
|
Tomás-Loba A, Bernardes de Jesus B, Mato JM, Blasco MA. A metabolic signature predicts biological age in mice. Aging Cell 2013; 12:93-101. [PMID: 23107558 DOI: 10.1111/acel.12025] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/19/2012] [Indexed: 01/01/2023] Open
Abstract
Our understanding of the mechanisms by which aging is produced is still very limited. Here, we have determined the sera metabolite profile of 117 wild-type mice of different genetic backgrounds ranging from 8 to 129 weeks of age. This has allowed us to define a robust metabolomic signature and a derived metabolomic score that reliably/accurately predicts the age of wild-type mice. In the case of telomerase-deficient mice, which have a shortened lifespan, their metabolomic score predicts older ages than expected. Conversely, in the case of mice that overexpress telomerase, their metabolic score corresponded to younger ages than expected. Importantly, telomerase reactivation late in life by using a TERT-based gene therapy recently described by us significantly reverted the metabolic profile of old mice to that of younger mice, further confirming an anti-aging role for telomerase. Thus, the metabolomic signature associated with natural mouse aging accurately predicts aging produced by telomere shortening, suggesting that natural mouse aging is in part produced by presence of short telomeres. These results indicate that the metabolomic signature is associated with the biological age rather than with the chronological age. This constitutes one of the first aging-associated metabolomic signatures in a mammalian organism.
Collapse
Affiliation(s)
- Antonia Tomás-Loba
- Telomeres and Telomerase Group; Molecular Oncology Program; Spanish National Cancer Research Centre (CNIO); Melchor Fernández Almagro 3; Madrid; E-28029; Spain
| | - Bruno Bernardes de Jesus
- Telomeres and Telomerase Group; Molecular Oncology Program; Spanish National Cancer Research Centre (CNIO); Melchor Fernández Almagro 3; Madrid; E-28029; Spain
| | - Jose M. Mato
- CIC bioGUNE, CIBERehd, Derio; Technology Park of Bizkaia; Derio; E-48160; Spain
| | - Maria A. Blasco
- Telomeres and Telomerase Group; Molecular Oncology Program; Spanish National Cancer Research Centre (CNIO); Melchor Fernández Almagro 3; Madrid; E-28029; Spain
| |
Collapse
|
35
|
Vera E, Bernardes de Jesus B, Foronda M, Flores JM, Blasco MA. Telomerase reverse transcriptase synergizes with calorie restriction to increase health span and extend mouse longevity. PLoS One 2013; 8:e53760. [PMID: 23349740 PMCID: PMC3551964 DOI: 10.1371/journal.pone.0053760] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 12/04/2012] [Indexed: 12/15/2022] Open
Abstract
Caloric restriction (CR), a reduction of food intake while avoiding malnutrition, can delay the onset of cancer and age-related diseases in several species, including mice. In addition, depending of the genetic background, CR can also increase or decrease mouse longevity. This has highlighted the importance of identifying the molecular pathways that interplay with CR in modulating longevity. Significant lifespan extension in mice has been recently achieved through over-expression of the catalytic subunit of mouse telomerase (mTERT) in a cancer protective background. Given the CR cancer-protective effects in rodents, we set to address here whether CR impacts on telomere length and synergizes with mTERT to extend mouse longevity. CR significantly decreased tumor incidence in TERT transgenic (TgTERT) mice and extended their lifespan compared to wild-type (WT) controls under the same diet, indicating a synergy between TgTERT and CR in increasing mouse longevity. In addition, longitudinal telomere length measurements in peripheral blood leukocytes from individual mice showed that CR resulted in maintenance and/or elongation telomeres in a percentage of WT mice, a situation that mimics telomere dynamics in TgTERT cohorts. These results demonstrate that CR attenuates telomere erosion associated to aging and that synergizes with TERT over-expression in increasing "health span" and extending mouse longevity.
Collapse
Affiliation(s)
- Elsa Vera
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Centre, Melchor Fernández Almagro 3, Madrid, Spain
| | - Bruno Bernardes de Jesus
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Centre, Melchor Fernández Almagro 3, Madrid, Spain
| | - Miguel Foronda
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Centre, Melchor Fernández Almagro 3, Madrid, Spain
| | - Juana M. Flores
- Animal Surgery and Medicine Department, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, Spain
| | - Maria A. Blasco
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Centre, Melchor Fernández Almagro 3, Madrid, Spain
- * E-mail:
| |
Collapse
|
36
|
Bernardes de Jesus B, Blasco MA. Potential of telomerase activation in extending health span and longevity. Curr Opin Cell Biol 2012; 24:739-43. [PMID: 23085234 DOI: 10.1016/j.ceb.2012.09.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 09/10/2012] [Accepted: 09/18/2012] [Indexed: 11/16/2022]
Abstract
The progressive increase in the elderly population worldwide has resulted in higher numbers of individuals affected by age-associated diseases, such as neurodegenerative and heart diseases, metabolic impairment, or cancer, with the subsequent burden for national health systems. Therapeutic interventions aimed to increase the quality of life at advanced age are visualized as important demands for the future, both at the level of individuals and society. Novel advances in telomerase function from several independent laboratories have resulted in potential new therapeutic strategies which appear as promising new venues to prevent cellular and tissue dysfunction and organismal decline, thereby increasing the so-called "health span". Here, we analyze these recent advances.
Collapse
Affiliation(s)
- Bruno Bernardes de Jesus
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, Madrid, E-28029, Spain
| | | |
Collapse
|
37
|
Vera E, Bernardes de Jesus B, Foronda M, Flores JM, Blasco MA. The rate of increase of short telomeres predicts longevity in mammals. Cell Rep 2012; 2:732-7. [PMID: 23022483 DOI: 10.1016/j.celrep.2012.08.023] [Citation(s) in RCA: 151] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 07/11/2012] [Accepted: 08/21/2012] [Indexed: 11/16/2022] Open
Abstract
Aberrantly short telomeres result in decreased longevity in both humans and mice with defective telomere maintenance. Normal populations of humans and mice present high interindividual variation in telomere length, but it is unknown whether this is associated with their lifespan potential. To address this issue, we performed a longitudinal telomere length study along the lifespan of wild-type and transgenic telomerase reverse transcriptase mice. We found that mouse telomeres shorten ∼100 times faster than human telomeres. Importantly, the rate of increase in the percentage of short telomeres, rather than the rate of telomere shortening per month, was a significant predictor of lifespan in both mouse cohorts, and those individuals who showed a higher rate of increase in the percentage of short telomeres were also the ones with a shorter lifespan. These findings demonstrate that short telomeres have a direct impact on longevity in mammals, and they highlight the importance of performing longitudinal telomere studies to predict longevity.
Collapse
Affiliation(s)
- Elsa Vera
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Center, Melchor Fernández Almagro 3, E-28029 Madrid, Spain
| | | | | | | | | |
Collapse
|
38
|
Richardson GD, Breault D, Horrocks G, Cormack S, Hole N, Owens WA. Telomerase expression in the mammalian heart. FASEB J 2012; 26:4832-40. [PMID: 22919071 PMCID: PMC3509052 DOI: 10.1096/fj.12-208843] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
While the mammalian heart has low, but functionally significant, levels of telomerase expression, the cellular population responsible remains incompletely characterized. This study aimed to identify the cell types responsible for cardiac telomerase activity in neonatal, adult, and cryoinjured adult hearts using transgenic mice expressing green fluorescent protein (GFP), driven by the promoter for murine telomerase reverse transcriptase (mTert), which is a necessary and rate-limiting component of telomerase. A rare population of mTert-GFP-expressing cells was identified that possessed all detectable cardiac telomerase RNA and telomerase activity. It was heterogeneous and included cells coexpressing markers of cardiomyocytic, endothelial, and mesenchymal lineages, putative cardiac stem cell markers, and, interestingly, cardiomyocytes with a differentiated phenotype. Quantification using both flow cytometry and immunofluorescence identified a significant decline in mTert-GFP cells in adult animals compared to neonates (∼9- and ∼20-fold, respectively). Cardiac injury resulted in a ∼6.45-fold expansion of this population (P<0.005) compared with sham-operated controls. This study identifies the cells responsible for cardiac telomerase activity, demonstrates a significant diminution with age but a marked response to injury, and, given the relationship between telomerase activity and stem cell populations, suggests that they represent a potential target for further investigation of cardiac regenerative potential.—Richardson, G. D., Breault, D., Horrocks, G., Cormack, S., Hole, N., Owens, W. A. Telomerase expression in the mammalian heart.
Collapse
Affiliation(s)
- Gavin D Richardson
- Institute of Genetic Medicine, International Centre for Life, Newcastle University, Newcastle upon Tyne, NE1 3BZ, UK.
| | | | | | | | | | | |
Collapse
|
39
|
Tümpel S, Rudolph KL. The role of telomere shortening in somatic stem cells and tissue aging: lessons from telomerase model systems. Ann N Y Acad Sci 2012; 1266:28-39. [DOI: 10.1111/j.1749-6632.2012.06547.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
40
|
Christensen K, Pedersen JK, Hjelmborg JVB, Vaupel JW, Stevnsner T, Holm NV, Skytthe A. Cancer and longevity--is there a trade-off? A study of cooccurrence in Danish twin pairs born 1900-1918. J Gerontol A Biol Sci Med Sci 2012; 67:489-94. [PMID: 22472962 DOI: 10.1093/gerona/gls087] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Animal models and a few human studies have suggested a complex interaction between cancer risk and longevity indicating a trade-off where low cancer risk is associated with accelerating aging phenotypes and, vice versa, that longevity potential comes with the cost of increased cancer risk. This hypothesis predicts that longevity in one twin is associated with increased cancer risk in the cotwin. METHODS A total of 4,354 twin pairs born 1900-1918 in Denmark were followed for mortality in the Danish Civil Registration System through 2008 and for cancer incidence in the period 1943-2008 through the Danish Cancer Registry. RESULTS The 8,139 twins who provided risk time for cancer occurrence entered the study between ages 24 and 43 (mean 33 years), and each participant was followed up to death, emigration, or at least 90 years of age. The total follow-up time was 353,410 person-years and, 2,524 cancers were diagnosed. A negative association between age at death of a twin and cancer incidence in the cotwin was found in the overall analyses as well as in the subanalysis stratified on sex, zygosity, and random selection of one twin from each twin pair. CONCLUSIONS This study did not find evidence of a cancer-longevity trade-off in humans. On the contrary, it suggested that longevity in one twin is associated with lower cancer incidence in the cotwin, indicating familial factors associated with both low cancer occurrence and longevity.
Collapse
Affiliation(s)
- Kaare Christensen
- The Danish Twin Registry, Epidemiology, Institute of Public Health, University of Southern Denmark, Odense C, Denmark.
| | | | | | | | | | | | | |
Collapse
|
41
|
Abstract
Human chromosome 8p23 is a region that has the most frequent heterozygosity in common human adult epithelial malignancies, but its major tumor suppressor gene(s) remain to be identified. Telomerase is activated in most human cancers and is critical for cancer cell growth. However, little is known about the significance of telomerase activation in chromosome instability and cancer initiation. The gene encoding the potent and highly conserved endogenous telomerase inhibitor PinX1 is located at human chromosome 8p23. However, the role of PinX1 in telomerase regulation and cancer development is not clear. Recent works from our group indicate that PinX1 is critical for maintaining telomere length at the optimal length. Furthermore, PinX1 is reduced in a large subset of human breast cancer tissues and cells. Significantly, PinX1 inhibition activates telomerase, and elongates telomeres, eventually leading to chromosome instability, all of which are abrogated by telomerase knockdown or knockout. Moreover, PinX1 allele loss causes majority of mice to develop a variety of epithelial cancers, which display chromosome instability and recapitulate to 8p23 allele loss in humans. These results indicate that PinX1 is a sought-after major tumor suppressor at human chromosome 8p23 that is essential for regulating telomerase activity and maintaining chromosome stability. These results suggest that inhibition of telomerase using PinX1 especially its telomerase inhibitory fragment or other methods might be used to treat cancers that have telomerase activation.
Collapse
Affiliation(s)
- Xiao Zhen Zhou
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
| |
Collapse
|
42
|
Jane-Wit D, Chun HJ. Mechanisms of dysfunction in senescent pulmonary endothelium. J Gerontol A Biol Sci Med Sci 2012; 67:236-41. [PMID: 22396472 DOI: 10.1093/gerona/glr248] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Age-dependent changes in pulmonary endothelium contribute to worsened clinical outcomes in elderly individuals. Due to altered pulmonary endothelial responses, older participants have increased vulnerability to infection-related sequelae, higher prevalence of pulmonary hypertension, mitigated DNA repair mechanisms, and attenuated parenchymal healing. Aberrant signaling in pulmonary endothelium undergird these clinical processes. In this review, we provide an overview of the work that has elucidated age-related molecular derangements in pulmonary endothelial cells. In particular, we summarize studies describing mishandling of intracellular reactive oxygen species, pathological nitric oxide signaling, and deficient recruitment of endothelial stem cell precursors. We conclude with a summary of potential future avenues of investigation. The signaling pathways associated with pulmonary endothelial senescence reviewed herein suggest a number of putative therapeutic drug targets. Further elucidation of the cellular processes associated with aging in the pulmonary endothelium may provide critical insights into the rational design of therapies that may subvert or even reverse the effects of aging on a molecular level.
Collapse
Affiliation(s)
- Daniel Jane-Wit
- Section of Cardiovascular Medicine, Yale University School of Medicine, 300 George St, Room 773K, New Haven, CT 06511, USA
| | | |
Collapse
|
43
|
Madan E, Gogna R, Bhatt M, Pati U, Kuppusamy P, Mahdi AA. Regulation of glucose metabolism by p53: emerging new roles for the tumor suppressor. Oncotarget 2011; 2:948-57. [PMID: 22248668 PMCID: PMC3282098 DOI: 10.18632/oncotarget.389] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Accepted: 12/20/2011] [Indexed: 01/10/2023] Open
Abstract
p53 is well known as the "guardian of the genome" for differentiated and neoplastic cells. p53 induces cell-cycle arrest and cell death after DNA damage and thus contributes to the maintenance of genomic stability. In addition to this tumor suppressor function for pro-oncogenic cells, p53 also plays an important role as the central regulator of stress response by maintaining cellular homeostasis at the molecular and biochemical level. p53 regulates aerobic respiration at the glycolytic and oxidative phosphorylation (OXPHOS) steps via transcriptional regulation of its downstream genes TP53-induced glycolysis regulator (TIGAR) and synthesis of cytochrome c oxidase (SCO2). p53 negatively regulates glycolysis through activation of TIGAR (an inhibitor of the fructose-2,6-bisphosphate). On the contrary p53 positively regulates OXPHOS through upregulation of SCO2, a member of the COX-2 assembly involved in the electron-transport chain. It is interesting to notice that p53 antagonistically regulates the inter-dependent glycolytic and OXPHOS cycles. It is important to understand whether the p53-mediated transcriptional regulation of TIGAR and SCO2 is temporally segregated in cancer cells and what is the relation between these paradoxical regulations of glycolytic pathway with the tumor suppressor activity of p53. In this review we will elucidate the importance of p53-mediated regulation of glycolysis and OXPHOS and its relation with the tumor suppressor function of p53. Further since cellular metabolism shares great relation with the process of aging we will also try and establish the role of p53 in regulation of aging via its transcriptional control of cellular metabolism.
Collapse
Affiliation(s)
- Esha Madan
- Department of Biochemistry, Chhatrapati Shahuji Maharaj Medical University, Lucknow, India
- Transcription and Human Biology Laboratory, School of Biotechnology, Jawaharlal Nehru University, New-Delhi, India
| | - Rajan Gogna
- Transcription and Human Biology Laboratory, School of Biotechnology, Jawaharlal Nehru University, New-Delhi, India
| | - Madan Bhatt
- Department of Radiotherapy and Chemotherapy, Chhatrapati Shahuji Maharaj Medical University, Lucknow, India
| | - Uttam Pati
- Transcription and Human Biology Laboratory, School of Biotechnology, Jawaharlal Nehru University, New-Delhi, India
| | - Periannan Kuppusamy
- Dorothy M Davis Heart and Lung Research institute, Dept. of Internal Medicine, Ohio State University, Columbus, OH, USA
| | - Abbas Ali Mahdi
- Department of Biochemistry, Chhatrapati Shahuji Maharaj Medical University, Lucknow, India
| |
Collapse
|
44
|
Nicholls C, Li H, Wang JQ, Liu JP. Molecular regulation of telomerase activity in aging. Protein Cell 2011; 2:726-38. [PMID: 21976062 DOI: 10.1007/s13238-011-1093-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2011] [Accepted: 08/30/2011] [Indexed: 11/25/2022] Open
Abstract
The process of aging is mitigated by the maintenance and repair of chromosome ends (telomeres), resulting in extended lifespan. This review examines the molecular mechanisms underlying the actions and regulation of the enzyme telomerase reverse transcriptase (TERT), which functions as the primary mechanism of telomere maintenance and regulates cellular life expectancy. Underpinning increased cell proliferation, telomerase is also a key factor in facilitating cancer cell immortalization. The review focuses on aspects of hormonal regulations of telomerase, and the intracellular pathways that converge to regulate telomerase activity with an emphasis on molecular interactions at protein and gene levels. In addition, the basic structure and function of two key telomerase enzyme components-the catalytic subunit TERT and the template RNA (TERC) are discussed briefly.
Collapse
Affiliation(s)
- Craig Nicholls
- Molecular Signalling Laboratory, Murdoch Childrens Research Institute, Parkville, Victoria 3052, Australia
| | | | | | | |
Collapse
|
45
|
Smoliga JM, Vang O, Baur JA. Challenges of translating basic research into therapeutics: resveratrol as an example. J Gerontol A Biol Sci Med Sci 2011; 67:158-67. [PMID: 21746739 DOI: 10.1093/gerona/glr062] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Basic science literature abounds with molecules that promise to ameliorate almost any disease, from curing cancer to slowing the aging process itself. However, most of these compounds will never even be evaluated in humans, let alone proven effective. Here, we use resveratrol as an example to highlight the enormous difficulties in understanding pharmacokinetics, determining side effects, and, ultimately, establishing mechanisms of action for a natural compound. Despite extensive interest and effort, and continuing promising results from basic science groups, very little is known even today about the effects of resveratrol in humans. Part of the problem is the unattractiveness of natural compounds to large, well-funded companies that could run clinical trials because developing their own molecules affords much greater protection for their intellectual property. In fact, selling unpatentable material motivates smaller nutraceutical companies to complicate the scientific problem even more--each creates its own proprietary blend, making it extremely difficult to compare their data with those of other companies, or of academic labs using pure compounds. But even beyond these problems lies a deeper one; resveratrol, and almost every natural compound, is likely to have many clinically relevant targets with different dose-response profiles, tissue distributions, and modifiers. Tackling this type of problem efficiently, and even beginning to address the spectrum of other molecules with claimed benefits, is likely to require the development of new paradigms and approaches. Examples include better molecular modeling to predict interactions, large-scale screens for toxic or other common effects, affinity-based methods to identify drug-interacting proteins, and better synthesis of existing data, including legislation to promote the release of trial results, and tracking of voluntary supplement usage. The evidence for benefits of resveratrol in humans remains too sparse to be conclusive; yet, the limited data that are available, combined with a growing list of animal studies, provide a strong justification for further study.
Collapse
Affiliation(s)
- James M Smoliga
- Department of Health and Physical Education, Human Physiology Laboratory, Marywood University, Scranton, Pennsylvania, USA
| | | | | |
Collapse
|
46
|
Is rate of skin wound healing associated with aging or longevity phenotype? Biogerontology 2011; 12:591-7. [DOI: 10.1007/s10522-011-9343-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Accepted: 05/30/2011] [Indexed: 10/18/2022]
|
47
|
Abstract
Telomeres protect the chromosome ends from unscheduled DNA repair and degradation. Telomeres are heterochromatic domains composed of repetitive DNA (TTAGGG repeats) bound to an array of specialized proteins. The length of telomere repeats and the integrity of telomere-binding proteins are both important for telomere protection. Furthermore, telomere length and integrity are regulated by a number of epigenetic modifications, thus pointing to higher order control of telomere function. In this regard, we have recently discovered that telomeres are transcribed generating long, non-coding RNAs, which remain associated with the telomeric chromatin and are likely to have important roles in telomere regulation. In the past, we showed that telomere length and the catalytic component of telomerase, Tert, are critical determinants for the mobilization of stem cells. These effects of telomerase and telomere length on stem cell behaviour anticipate the premature ageing and cancer phenotypes of telomerase mutant mice. Recently, we have demonstrated the anti-ageing activity of telomerase by forcing telomerase expression in mice with augmented cancer resistance. Shelterin is the major protein complex bound to mammalian telomeres; however, its potential relevance for cancer and ageing remained unaddressed to date. To this end, we have generated mice conditionally deleted for the shelterin proteins TRF1, TPP1 and Rap1. The study of these mice demonstrates that telomere dysfunction, even if telomeres are of a normal length, is sufficient to produce premature tissue degeneration, acquisition of chromosomal aberrations and initiation of neoplastic lesions. These new mouse models, together with the telomerase-deficient mouse model, are valuable tools for understanding human pathologies produced by telomere dysfunction.
Collapse
Affiliation(s)
- Luis E Donate
- Telomeres and Telomerase Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro, 3, 28029 Madrid, Spain
| | | |
Collapse
|
48
|
Abstract
Skin is a self-renewing tissue that is required to go through extensive proliferation throughout the lifespan of an organism. Telomere shortening acts as a mitotic clock that prevents aberrant proliferation such as cancer. A consequence of this protection is cellular senescence and ageing. The telomerase enzyme complex maintains telomere length in germline cells and in cancer cells. Telomerase is also active in certain somatic cells such as those in the epidermis but is almost undetectable in the dermis. Increasing evidence indicates that telomerase plays a significant role in maintenance of skin function and proliferation. Mutations in telomerase component genes in the disease dyskeratosis congenita result in numerous epidermal abnormalities. Studies also indicate that telomerase activity in epidermal stem cells might have roles that go beyond telomere elongation. Telomeres in skin cells may be particularly susceptible to accelerated shortening because of both proliferation and DNA-damaging agents such as reactive oxygen species. Skin might present an accessible tissue for manipulation of telomerase activity and telomere length with the potential of ameliorating skin diseases associated with ageing.
Collapse
Affiliation(s)
- Erin M Buckingham
- Department of Microbiology, University of Iowa, Iowa City, IA 52242, USA
| | | |
Collapse
|
49
|
Mather KA, Jorm AF, Parslow RA, Christensen H. Is telomere length a biomarker of aging? A review. J Gerontol A Biol Sci Med Sci 2010; 66:202-13. [PMID: 21030466 DOI: 10.1093/gerona/glq180] [Citation(s) in RCA: 283] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Telomeres, the DNA-protein structures located at the ends of chromosomes, have been proposed to act as a biomarker of aging. In this review, the human evidence that telomere length is a biomarker of aging is evaluated. Although telomere length is implicated in cellular aging, the evidence suggesting telomere length is a biomarker of aging in humans is equivocal. More studies examining the relationships between telomere length and mortality and with measures that decline with "normal" aging in community samples are required. These studies would benefit from longitudinal measures of both telomere length and aging-related parameters.
Collapse
Affiliation(s)
- Karen Anne Mather
- Centre for Mental Health Research, Australian National University, Canberra, Australia.
| | | | | | | |
Collapse
|
50
|
|