201
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Sunderland P, Augustyniak J, Lenart J, Bużańska L, Carlessi L, Delia D, Sikora E. ATM-deficient neural precursors develop senescence phenotype with disturbances in autophagy. Mech Ageing Dev 2020; 190:111296. [PMID: 32621937 DOI: 10.1016/j.mad.2020.111296] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 05/29/2020] [Accepted: 06/22/2020] [Indexed: 01/09/2023]
Abstract
ATM is a kinase involved in DNA damage response (DDR), regulation of response to oxidative stress, autophagy and mitophagy. Mutations in the ATM gene in humans result in ataxi A-Telangiectasia disease (A-T) characterized by a variety of symptoms with neurodegeneration and premature ageing among them. Since brain is one of the most affected organs in A-T, we have focused on senescence of neural progenitor cells (NPCs) derived from A-T reprogrammed fibroblasts. Accordingly, A-T NPCs obtained through neural differentiation of iPSCs in 5% oxygen possessed some features of senescence including increased activity of SA-β-gal and secretion of IL6 and IL8 in comparison to control NPCs. This phenotype of A-T NPC was accompanied by elevated oxidative stress. A-T NPCs exhibited symptoms of impaired autophagy and mitophagy with lack of response to chloroquine treatment. Additional sources of oxidative stress like increased oxygen concentration (20 %) and H2O2 respectively aggravated the phenotype of senescence and additionally disturbed the process of mitophagy. In both cases only A-T NPCs reacted to the treatment. We conclude that oxidative stress may be responsible for the phenotype of senescence and impairment of autophagy in A-T NPCs. Our results point to senescent A-T cells as a potential therapeutic target in this disease.
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Affiliation(s)
- Piotr Sunderland
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
| | - Justyna Augustyniak
- Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Jacek Lenart
- Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Leonora Bużańska
- Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Luigi Carlessi
- Department of Research, Fondazione IRCCS Istituto Nazionale Tumori, Milan, Italy
| | - Domenico Delia
- Department of Research, Fondazione IRCCS Istituto Nazionale Tumori, Milan, Italy; IFOM, FIRC Institute of Molecular Oncology, Milano, Italy
| | - Ewa Sikora
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
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202
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Papadopoulos D, Magliozzi R, Mitsikostas DD, Gorgoulis VG, Nicholas RS. Aging, Cellular Senescence, and Progressive Multiple Sclerosis. Front Cell Neurosci 2020; 14:178. [PMID: 32694983 PMCID: PMC7338849 DOI: 10.3389/fncel.2020.00178] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 05/22/2020] [Indexed: 12/12/2022] Open
Abstract
Aging is one of the most important risk factors for the development of several neurodegenerative diseases including progressive multiple sclerosis (MS). Cellular senescence (CS) is a key biological process underlying aging. Several stressors associated with aging and MS pathology, such as oxidative stress, mitochondrial dysfunction, cytokines and replicative exhaustion are known triggers of cellular senescence. Senescent cells exhibit stereotypical metabolic and functional changes, which include cell-cycle arrest and acquiring a pro-inflammatory phenotype secreting cytokines, growth factors, metalloproteinases and reactive oxygen species. They accumulate with aging and can convert neighboring cells to senescence in a paracrine manner. In MS, accelerated cellular senescence may drive disease progression by promoting chronic non-remitting inflammation, loss or altered immune, glial and neuronal function, failure of remyelination, impaired blood-brain barrier integrity and ultimately neurodegeneration. Here we discuss the evidence linking cellular senescence to the pathogenesis of MS and the putative role of senolytic and senomorphic agents as neuroprotective therapies in tackling disease progression.
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Affiliation(s)
- Dimitrios Papadopoulos
- Molecular Carcinogenesis Group, Laboratory of Histology and Embryology, School of Health Sciences, National and Kapodistrian University of Athens, Athens, Greece
| | - Roberta Magliozzi
- Department of Neuroscience, Biomedicine and Movement, University of Verona, Verona, Italy
| | - Dimos D Mitsikostas
- First Department of Neurology, Aeginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Vassilis G Gorgoulis
- Molecular Carcinogenesis Group, Laboratory of Histology and Embryology, School of Health Sciences, National and Kapodistrian University of Athens, Athens, Greece
| | - Richard S Nicholas
- Department of Neuroinflammation and Neurodegeneration, Faculty of Medicine, Imperial College London, London, United Kingdom.,Department of Visual Neuroscience, Faculty of Brain Sciences, Institute of Ophthalmology, University College London, London, United Kingdom
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203
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Proshkina E, Shaposhnikov M, Moskalev A. Genome-Protecting Compounds as Potential Geroprotectors. Int J Mol Sci 2020; 21:E4484. [PMID: 32599754 PMCID: PMC7350017 DOI: 10.3390/ijms21124484] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 02/06/2023] Open
Abstract
Throughout life, organisms are exposed to various exogenous and endogenous factors that cause DNA damages and somatic mutations provoking genomic instability. At a young age, compensatory mechanisms of genome protection are activated to prevent phenotypic and functional changes. However, the increasing stress and age-related deterioration in the functioning of these mechanisms result in damage accumulation, overcoming the functional threshold. This leads to aging and the development of age-related diseases. There are several ways to counteract these changes: 1) prevention of DNA damage through stimulation of antioxidant and detoxification systems, as well as transition metal chelation; 2) regulation of DNA methylation, chromatin structure, non-coding RNA activity and prevention of nuclear architecture alterations; 3) improving DNA damage response and repair; 4) selective removal of damaged non-functional and senescent cells. In the article, we have reviewed data about the effects of various trace elements, vitamins, polyphenols, terpenes, and other phytochemicals, as well as a number of synthetic pharmacological substances in these ways. Most of the compounds demonstrate the geroprotective potential and increase the lifespan in model organisms. However, their genome-protecting effects are non-selective and often are conditioned by hormesis. Consequently, the development of selective drugs targeting genome protection is an advanced direction.
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Affiliation(s)
- Ekaterina Proshkina
- Laboratory of Geroprotective and Radioprotective Technologies, Institute of Biology, Komi Science Centre, Ural Branch, Russian Academy of Sciences, 28 Kommunisticheskaya st., 167982 Syktyvkar, Russia; (E.P.); (M.S.)
| | - Mikhail Shaposhnikov
- Laboratory of Geroprotective and Radioprotective Technologies, Institute of Biology, Komi Science Centre, Ural Branch, Russian Academy of Sciences, 28 Kommunisticheskaya st., 167982 Syktyvkar, Russia; (E.P.); (M.S.)
| | - Alexey Moskalev
- Laboratory of Geroprotective and Radioprotective Technologies, Institute of Biology, Komi Science Centre, Ural Branch, Russian Academy of Sciences, 28 Kommunisticheskaya st., 167982 Syktyvkar, Russia; (E.P.); (M.S.)
- Pitirim Sorokin Syktyvkar State University, 55 Oktyabrsky prosp., 167001 Syktyvkar, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
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204
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Zhang D, Yu K, Yang J, Xie S, Yang J, Tan L. Senolytic controls bone marrow mesenchymal stem cells fate improving bone formation. Am J Transl Res 2020; 12:3078-3088. [PMID: 32655832 PMCID: PMC7344065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 06/03/2020] [Indexed: 06/11/2023]
Abstract
Bone marrow mesenchymal stem cells (BMSCs) are multipotential stem cells. Osteoporosis is an age-related disorder characterized by increased marrow fat accumulation and declined bone formation. Aging is an important initial factor of bone mass loss. So, manipulating the senescence of BMSCs is a considerable therapeutic target for osteoporosis treatment. To investigate the role of senolytics on regulating the differential fate of senescent BMSCs. Rat BMSCs were isolated and identified by immunofluorescence and multilineage differentiation assay. Quercetin was used to clean senescent BMSCs. Cell counting kit-8 (CCK-8) and colony formation assay was used to evaluate the cellular proliferation. While the cellular migration was detected by the scratch wound healing assay and transwell assay. And the osteogenesis assay and adipogenesis assay were used to determine the differential fate of BMSCs. BMSCs exhibited stemness. Eliminating senescent BMSCs improved the proliferation of BMSCs. But the quercetin treatment made no difference in cellular migration. And the osteogenic potential was increased while the adipogenic potential was decreased when the senescent BMSCs were cleaned by quercetin treatment. Our results demonstrate that cleaning senescent BMSCs improves the proliferation and osteogenesis of BMSCs as well as inhibits the adipogenesis of BMSCs, which provides a novel therapeutic target for the treatment of osteoporosis.
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Affiliation(s)
- Dianying Zhang
- Department of Orthopedics and Trauma, People’s Hospital, Peking UniversityBeijing 100044, China
| | - Kai Yu
- Department of Orthopedics, Tianjin Fifth Central HospitalTianjin 300450, China
| | - Jie Yang
- Department of Orthopedics, Tianjin Fifth Central HospitalTianjin 300450, China
| | - Shangding Xie
- Department of Orthopedics, Tianjin Fifth Central HospitalTianjin 300450, China
| | - Jian Yang
- Department of Orthopedics, Tianjin Fifth Central HospitalTianjin 300450, China
| | - Li Tan
- Department of Orthopedics, Tianjin Fifth Central HospitalTianjin 300450, China
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205
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Norton EJ, Bridges LR, Kenyon LC, Esiri MM, Bennett DC, Hainsworth AH. Cell Senescence and Cerebral Small Vessel Disease in the Brains of People Aged 80 Years and Older. J Neuropathol Exp Neurol 2020; 78:1066-1072. [PMID: 31553444 DOI: 10.1093/jnen/nlz088] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 07/21/2019] [Indexed: 12/17/2022] Open
Abstract
Cerebral small vessel disease (cSVD) in penetrating arteries is a major cause of age-related morbidity. Cellular senescence is a molecular process targeted by novel senolytic drugs. We quantified senescence in penetrating arteries and tested whether myocyte senescence was associated with cSVD. We immunolabeled subcortical white matter of older persons (age 80-96 years, n = 60) with minimal AD, using antibodies to 2 established senescence markers (H3K9me3, γH2AX) and a myocyte marker (hSMM). Within the walls of penetrating arteries (20-300 µm), we quantified senescence-associated heterochromatic foci (SAHF)-positive nuclei, cell density (nuclei/µm2), and sclerotic index (SI). Senescent-appearing mural cells were present in small arteries of all cases. cSVD cases exhibited a lower proportion of senescent-appearing cells and lower area fraction (AF%) of SAHF-positive nuclei compared to controls (p = 0.014, 0.016, respectively). cSVD severity and SI both correlated negatively with AF% (p = 0.013, 0.002, respectively). Mural cell density was lower (p < 0.001) and SI higher (p < 0.001) in cSVD, relative to controls. In conclusion, senescent myocyte-like cells were universal in penetrating arteries of an AD-free cohort aged 80 years and older. Senescent-appearing nuclei were more common in persons aged 80 years and older without cSVD compared to cSVD cases, indicating caution in senolytic drug prescribing. Myocyte senescence and cSVD may represent alternative vessel fates in the aging human brain.
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Affiliation(s)
- Emma J Norton
- Molecular and Clinical Sciences Research Institute, St George's, University of London, London, UK; Department of Cellular Pathology, St George's University Hospitals NHS Foundation Trust, London, UK; Department of Pathology, Anatomy & Cell Biology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania; Department of Neuropathology, Oxford-Radcliffe NHS Trust, Oxford, UK; Department of Clinical Neurology, Oxford University, John Radcliffe Hospital, Oxford, UK; and Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Leslie R Bridges
- Molecular and Clinical Sciences Research Institute, St George's, University of London, London, UK; Department of Cellular Pathology, St George's University Hospitals NHS Foundation Trust, London, UK; Department of Pathology, Anatomy & Cell Biology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania; Department of Neuropathology, Oxford-Radcliffe NHS Trust, Oxford, UK; Department of Clinical Neurology, Oxford University, John Radcliffe Hospital, Oxford, UK; and Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Lawrence C Kenyon
- Molecular and Clinical Sciences Research Institute, St George's, University of London, London, UK; Department of Cellular Pathology, St George's University Hospitals NHS Foundation Trust, London, UK; Department of Pathology, Anatomy & Cell Biology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania; Department of Neuropathology, Oxford-Radcliffe NHS Trust, Oxford, UK; Department of Clinical Neurology, Oxford University, John Radcliffe Hospital, Oxford, UK; and Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Margaret M Esiri
- Molecular and Clinical Sciences Research Institute, St George's, University of London, London, UK; Department of Cellular Pathology, St George's University Hospitals NHS Foundation Trust, London, UK; Department of Pathology, Anatomy & Cell Biology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania; Department of Neuropathology, Oxford-Radcliffe NHS Trust, Oxford, UK; Department of Clinical Neurology, Oxford University, John Radcliffe Hospital, Oxford, UK; and Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Dorothy C Bennett
- Molecular and Clinical Sciences Research Institute, St George's, University of London, London, UK; Department of Cellular Pathology, St George's University Hospitals NHS Foundation Trust, London, UK; Department of Pathology, Anatomy & Cell Biology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania; Department of Neuropathology, Oxford-Radcliffe NHS Trust, Oxford, UK; Department of Clinical Neurology, Oxford University, John Radcliffe Hospital, Oxford, UK; and Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Atticus H Hainsworth
- Molecular and Clinical Sciences Research Institute, St George's, University of London, London, UK; Department of Cellular Pathology, St George's University Hospitals NHS Foundation Trust, London, UK; Department of Pathology, Anatomy & Cell Biology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania; Department of Neuropathology, Oxford-Radcliffe NHS Trust, Oxford, UK; Department of Clinical Neurology, Oxford University, John Radcliffe Hospital, Oxford, UK; and Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
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206
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Han X, Zhang T, Liu H, Mi Y, Gou X. Astrocyte Senescence and Alzheimer's Disease: A Review. Front Aging Neurosci 2020; 12:148. [PMID: 32581763 PMCID: PMC7297132 DOI: 10.3389/fnagi.2020.00148] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 05/01/2020] [Indexed: 01/10/2023] Open
Abstract
Astrocytes are the largest group of glial cells in the brain and participate in several essential functions of the central nervous system (CNS). Disruption of their normal physiological function can lead to metabolism disequilibrium and the pathology of CNS. As an important mechanism of aging, cellular senescence has been considered as a primary inducing factor of age-associated neurodegenerative disorders. Senescent astrocytes showed decreased normal physiological function and increased secretion of senescence-associated secretory phenotype (SASP) factors, which contribute to Aβ accumulation, tau hyperphosphorylation, and the deposition of neurofibrillary tangles (NFTs) in Alzheimer’s disease (AD). Astrocyte senescence also leads to a number of detrimental effects, including induced glutamate excitotoxicity, impaired synaptic plasticity, neural stem cell loss, and blood–brain barrier (BBB) dysfunction. In this review article, we have summarized the growing findings regarding astrocyte senescence and its putative role in the pathologic progress of AD. Additionally, we also focus on the significance of targeting astrocyte senescence as a novel and feasible therapeutic approach for AD.
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Affiliation(s)
- Xiaojuan Han
- Shaanxi Key Laboratory of Brain Disorders & Institute of Basic and Translational Medicine, Xi'an Medical University, Xi'an, China
| | - Tianying Zhang
- Shaanxi Key Laboratory of Brain Disorders & Institute of Basic and Translational Medicine, Xi'an Medical University, Xi'an, China
| | - Huanhuan Liu
- Shaanxi Key Laboratory of Brain Disorders & Institute of Basic and Translational Medicine, Xi'an Medical University, Xi'an, China
| | - Yajing Mi
- Shaanxi Key Laboratory of Brain Disorders & Institute of Basic and Translational Medicine, Xi'an Medical University, Xi'an, China
| | - Xingchun Gou
- Shaanxi Key Laboratory of Brain Disorders & Institute of Basic and Translational Medicine, Xi'an Medical University, Xi'an, China
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207
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Walton CC, Begelman D, Nguyen W, Andersen JK. Senescence as an Amyloid Cascade: The Amyloid Senescence Hypothesis. Front Cell Neurosci 2020; 14:129. [PMID: 32508595 PMCID: PMC7248249 DOI: 10.3389/fncel.2020.00129] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 04/20/2020] [Indexed: 01/10/2023] Open
Abstract
Due to their postmitotic status, the potential for neurons to undergo senescence has historically received little attention. This lack of attention has extended to some non-postmitotic cells as well. Recently, the study of senescence within the central nervous system (CNS) has begun to emerge as a new etiological framework for neurodegenerative diseases such as Alzheimer’s disease (AD) and Parkinson’s disease (PD). The presence of senescent cells is known to be deleterious to non-senescent neighboring cells via development of a senescence-associated secretory phenotype (SASP) which includes the release of inflammatory, oxidative, mitogenic, and matrix-degrading factors. Senescence and the SASP have recently been hailed as an alternative to the amyloid cascade hypothesis and the selective killing of senescence cells by senolytic drugs as a substitute for amyloid beta (Aß) targeting antibodies. Here we call for caution in rejecting the amyloid cascade hypothesis and to the dismissal of Aß antibody intervention at least in early disease stages, as Aß oligomers (AßO), and cellular senescence may be inextricably linked. We will review literature that portrays AßO as a stressor capable of inducing senescence. We will discuss research on the potential role of secondary senescence, a process by which senescent cells induce senescence in neighboring cells, in disease progression. Once this seed of senescent cells is present, the elimination of senescence-inducing stressors like Aß would likely be ineffective in abrogating the spread of senescence. This has potential implications for when and why AßO clearance may or may not be effective as a therapeutic for AD. The selective killing of senescent cells by the immune system via immune surveillance naturally curtails the SASP and secondary senescence outside the CNS. Immune privilege restricts the access of peripheral immune cells to the brain parenchyma, making the brain a safe harbor for the spread of senescence and the SASP. However, an increasingly leaky blood brain barrier (BBB) compromises immune privilege in aging AD patients, potentially enabling immune infiltration that could have detrimental consequences in later AD stages. Rather than an alternative etiology, senescence itself may constitute an essential component of the cascade in the amyloid cascade hypothesis.
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Affiliation(s)
- Chaska C Walton
- Buck Institute for Research on Aging, Novato, CA, United States
| | - David Begelman
- Buck Institute for Research on Aging, Novato, CA, United States
| | - Wynnie Nguyen
- Buck Institute for Research on Aging, Novato, CA, United States
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208
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Long-lived post-mitotic cell aging: is a telomere clock at play? Mech Ageing Dev 2020; 189:111256. [PMID: 32380018 DOI: 10.1016/j.mad.2020.111256] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/25/2020] [Accepted: 04/27/2020] [Indexed: 12/27/2022]
Abstract
Senescence is a cellular response to stress for both dividing and post-mitotic cells. Noteworthy, long-lived post-mitotic cells (collectively named LLPMCs), which can live for decades in the organism, can exhibit a distinct type of cellular aging characterized by a progressive functional decline not associated to an overt senescence phenotype. The age-related drivers of senescence and aging in LLPMCs remain largely unknown. There is evidence that an increased production of reactive oxygen species (ROS) due to dysfunctional mitochondria, coupled with an inherent inability of cellular-degradation mechanisms to remove damaged molecules, is responsible for senescence and aging in LLPMC. Although telomeric DNA shortening, by nature linked to cell division, is generally not considered as a driver of LLPMC aging and senescence, we discuss recent reports revealing the existence of age-related telomere changes in LLPMC. These findings reveal unexpected roles for telomeres in LLPMC function and invite us to consider the hypothesis of a complex telomere clock involved in both dividing and non-dividing cell aging.
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209
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Khosla S, Farr JN, Tchkonia T, Kirkland JL. The role of cellular senescence in ageing and endocrine disease. Nat Rev Endocrinol 2020; 16:263-275. [PMID: 32161396 PMCID: PMC7227781 DOI: 10.1038/s41574-020-0335-y] [Citation(s) in RCA: 240] [Impact Index Per Article: 60.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/14/2020] [Indexed: 12/19/2022]
Abstract
With the ageing of the global population, interest is growing in the 'geroscience hypothesis', which posits that manipulation of fundamental ageing mechanisms will delay (in parallel) the appearance or severity of multiple chronic, non-communicable diseases, as these diseases share the same underlying risk factor - namely, ageing. In this context, cellular senescence has received considerable attention as a potential target in preventing or treating multiple age-related diseases and increasing healthspan. Here we review mechanisms of cellular senescence and approaches to target this pathway therapeutically using 'senolytic' drugs that kill senescent cells or inhibitors of the senescence-associated secretory phenotype (SASP). Furthermore, we highlight the evidence that cellular senescence has a causative role in multiple diseases associated with ageing. Finally, we focus on the role of cellular senescence in a number of endocrine diseases, including osteoporosis, metabolic syndrome and type 2 diabetes mellitus, as well as other endocrine conditions. Although much remains to be done, considerable preclinical evidence is now leading to the initiation of proof-of-concept clinical trials using senolytics for several endocrine and non-endocrine diseases.
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Affiliation(s)
- Sundeep Khosla
- Division of Endocrinology, Mayo Clinic, Rochester, MN, USA.
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN, USA.
| | - Joshua N Farr
- Division of Endocrinology, Mayo Clinic, Rochester, MN, USA
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN, USA
| | - Tamara Tchkonia
- Division of Endocrinology, Mayo Clinic, Rochester, MN, USA
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN, USA
| | - James L Kirkland
- Division of Endocrinology, Mayo Clinic, Rochester, MN, USA.
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN, USA.
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210
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Richard SA, Jia-Hao Z. Elucidating the pathogenic and biomarker potentials of FOXG1 in glioblastoma. Oncol Rev 2020; 14:444. [PMID: 32395201 PMCID: PMC7204822 DOI: 10.4081/oncol.2020.444] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 03/20/2020] [Indexed: 12/11/2022] Open
Abstract
Glioblastoma (GB) is an extremely pugnacious brain cancer originating from neural stem (NS) cell-like cells. Forkhead box G1 (FOXG1; previously recognized as BF-1, qin, Chicken Brain Factor 1, or XBF-1 and renamed FOXG1 for mouse and human, and FoxG1 for other chordates) is an evolutionary preserved transcription factor driven from the forkhead box group of proteins FOXG1 modulates the speed of neurogenesis by maintaining progenitor cells in a proliferative mode as well as obstructing their differentiation into neurons during the initial periods of cortical formation. FOXG1 has been implicated in the formation of central nervous system (CNS) tumors and precisely GBs. Pathophysiologically, joint actions of FOXG1 and phosphatidylinositol- 3-kinases (PI3K) intermediate in intrinsic resistance of human GB cells to transforming growth factor-beta (TGF-β) stimulation of cyclin-dependent kinase inhibitor 1(p21Cip1) as well as growth inhibition. FOXG1 and NOTCH signaling pathways may functionally interrelate at different stages to facilitate gliomagenesis. Furthermore, FoxG1 actively contributed to the formation of transcription suppression complexes with corepressors of the Groucho/transducin-like Enhancer of split (Gro/TLEs). Also, FOXG1 was stimulated by Gro/TLE1 and abridged by Grg6. FOXG1 silencing in brain tumor-initiating cells (BTICs) also resulted in diminished secretion of markers characteristic undifferentiated natural neural stem/progenitor cells (NSPC) states, such as Oligodendrocyte transcription factor (OLIG2), (sex determining region Y)-box 2. (SOX2) and B lymphoma Mo-MLV insertion region 1 homolog (BMI1). This review therefore focuses on the pathogenic and biomarker potentials of FOXG1 in GB.
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Affiliation(s)
- Seidu A Richard
- Department of Neurosurgery, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu Province, P.R. China.,Department of Medicine, Princefield University, Ho-Volta Region, Ghana, West Africa
| | - Zhou Jia-Hao
- Department of Neurosurgery, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu Province, P.R. China
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211
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Dungan CM, Peck BD, Walton RG, Huang Z, Bamman MM, Kern PA, Peterson CA. In vivo analysis of γH2AX+ cells in skeletal muscle from aged and obese humans. FASEB J 2020; 34:7018-7035. [PMID: 32246795 DOI: 10.1096/fj.202000111rr] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 03/12/2020] [Accepted: 03/17/2020] [Indexed: 12/25/2022]
Abstract
Over the past 20 years, various identifiers of cellular senescence have been used to quantify the abundance of these cells in different tissues. These include classic markers such as p16, senescence-associated β-gal, and γH2AX, in addition to more recent markers (Sudan Black B and HMGB1). In vivo data on the usefulness of these markers in skeletal muscle are very limited and inconsistent. In the present study, we attempted to identify senescent cells in frozen human skeletal muscle biopsies using these markers to determine the effects of age and obesity on senescent cell burden; however, we were only able to assess the abundance of DNA-damaged nuclei using γH2AX immunohistochemistry. The abundance of γH2AX+ cells, including satellite cells, was not higher in muscle from old compared to young individuals; however, γH2AX+ cells were higher with obesity. Additionally, terminally differentiated, postmitotic myofiber nuclei from obese individuals had elevated γH2AX abundance compared to muscle from lean individuals. Analyses of gene expression support the conclusion that the elevated DNA damage and the senescence-associated secretory phenotype are preferentially associated with obesity in skeletal muscle. These data implicate obesity as a larger contributor to DNA damage in skeletal muscle than aging; however, more sensitive senescence markers for human skeletal muscle are needed to determine if these cells are in fact senescent.
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Affiliation(s)
- Cory M Dungan
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY, USA.,Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Bailey D Peck
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY, USA.,Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - R Grace Walton
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY, USA.,Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
| | - Zhengyan Huang
- Department of Biostatistics, College of Public Health, University of Kentucky, Lexington, KY, USA
| | - Marcas M Bamman
- Department of Cell, Developmental, and Integrative Biology, School of Medicine, University of Alabama, Birmingham, AL, USA.,Geriatric Research, Education, and Clinical Center, Birmingham VA Medical Center, Birmingham, AL, USA
| | - Philip A Kern
- Department of Internal Medicine/Endocrinology, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Charlotte A Peterson
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY, USA.,Center for Muscle Biology, University of Kentucky, Lexington, KY, USA
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212
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Ding X, Liu X, Wang F, Wang F, Geng X. Role of Senescence and Neuroprotective Effects of Telomerase in Neurodegenerative Diseases. Rejuvenation Res 2020; 23:150-158. [DOI: 10.1089/rej.2018.2115] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Xuelu Ding
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Medical University, Tianjin, China
| | - Xuewen Liu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Medical University, Tianjin, China
| | - Feng Wang
- Department of Genetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Fei Wang
- Department of Neurology, General Hospital, Tianjin Medical University, Tianjin, China
| | - Xin Geng
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Medical University, Tianjin, China
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213
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Abstract
Life expectancy has increased substantially over the last few decades, leading to a worldwide increase in the prevalence and burden of aging-associated diseases. Recent evidence has proven that cellular senescence contributes substantially to the development of these disorders. Cellular senescence is a state of cell cycle arrest with suppressed apoptosis and concomitant secretion of multiple bioactive factors (the senescence-associated secretory phenotype-SASP) that plays a physiological role in embryonic development and healing processes. However, DNA damage and oxidative stress that occur during aging cause the accumulation of senescent cells, which through their SASP bring about deleterious effects on multiple organ and systemic functions. Ablation of senescent cells through genetic or pharmacological means leads to improved life span and health span in animal models, and preliminary evidence suggests it may also have a positive impact on human health. Thus, strategies to reduce or eliminate the burden of senescent cells or their products have the potential to impact multiple clinical outcomes with a single intervention. In this review, we touch upon the basics of cell senescence and summarize the current state of development of therapies against cell senescence for human use.
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214
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Gao Z, Gao H, Zheng D, Xu T, Chen Y, Liang C, Wang L, Ding D, Yang Z. β-galactosidase responsive AIE fluorogene for identification and removal of senescent cancer cells. Sci China Chem 2020. [DOI: 10.1007/s11426-019-9659-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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215
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Martínez-Cué C, Rueda N. Cellular Senescence in Neurodegenerative Diseases. Front Cell Neurosci 2020; 14:16. [PMID: 32116562 PMCID: PMC7026683 DOI: 10.3389/fncel.2020.00016] [Citation(s) in RCA: 150] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 01/21/2020] [Indexed: 01/10/2023] Open
Abstract
Cellular senescence is a homeostatic biological process characterized by a permanent state of cell cycle arrest that can contribute to the decline of the regenerative potential and function of tissues. The increased presence of senescent cells in different neurodegenerative diseases suggests the contribution of senescence in the pathophysiology of these disorders. Although several factors can induce senescence, DNA damage, oxidative stress, neuroinflammation, and altered proteostasis have been shown to play a role in its onset. Oxidative stress contributes to accelerated aging and cognitive dysfunction stages affecting neurogenesis, neuronal differentiation, connectivity, and survival. During later life stages, it is implicated in the progression of cognitive decline, synapse loss, and neuronal degeneration. Also, neuroinflammation exacerbates oxidative stress, synaptic dysfunction, and neuronal death through the harmful effects of pro-inflammatory cytokines on cell proliferation and maturation. Both oxidative stress and neuroinflammation can induce DNA damage and alterations in DNA repair that, in turn, can exacerbate them. Another important feature associated with senescence is altered proteostasis. Because of the disruption in the function and balance of the proteome, senescence can modify the proper synthesis, folding, quality control, and degradation rate of proteins producing, in some diseases, misfolded proteins or aggregation of abnormal proteins. There is an extensive body of literature that associates cellular senescence with several neurodegenerative disorders including Alzheimer’s disease (AD), Down syndrome (DS), and Parkinson’s disease (PD). This review summarizes the evidence of the shared neuropathological events in these neurodegenerative diseases and the implication of cellular senescence in their onset or aggravation. Understanding the role that cellular senescence plays in them could help to develop new therapeutic strategies.
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Affiliation(s)
- Carmen Martínez-Cué
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Spain
| | - Noemí Rueda
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Cantabria, Santander, Spain
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216
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Tuttle CSL, Waaijer MEC, Slee‐Valentijn MS, Stijnen T, Westendorp R, Maier AB. Cellular senescence and chronological age in various human tissues: A systematic review and meta-analysis. Aging Cell 2020; 19:e13083. [PMID: 31808308 PMCID: PMC6996941 DOI: 10.1111/acel.13083] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 10/26/2019] [Accepted: 11/01/2019] [Indexed: 01/10/2023] Open
Abstract
Senescent cells in tissues and organs are considered to be pivotal to not only the aging process but also the onset of chronic disease. Accumulating evidence from animal experiments indicates that the magnitude of senescence can vary within and between aged tissue samples from the same animal. However, whether this variation in senescence translates across to human tissue samples is unknown. To address this fundamental question, we have conducted a systematic review and meta‐analysis of all available literature investigating the magnitude of senescence and its association with chronological age in human tissue samples. While senescence is higher in aged tissue samples, the magnitude of senescence varies considerably depending upon tissue type, tissue section, and marker used to detect senescence. These findings echo animal experiments demonstrating that senescence levels may vary between organs within the same animal.
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Affiliation(s)
- Camilla S. L. Tuttle
- Department of Medicine and Aged Care Royal Melbourne Hospital University of Melbourne Melbourne Vic. Australia
| | - Mariette E. C. Waaijer
- Department of Gerontology and Geriatrics Leiden University Medical Center Leiden The Netherlands
| | | | - Theo Stijnen
- Department of Biomedical Data Sciences Leiden University Medical Center Leiden The Netherlands
| | - Rudi Westendorp
- Department of Public Health and Centre for Healthy Ageing University of Copenhagen Copenhagen Denmark
| | - Andrea B. Maier
- Department of Medicine and Aged Care Royal Melbourne Hospital University of Melbourne Melbourne Vic. Australia
- Department of Human Movement Sciences Faculty of Behavioural and Movement Sciences Amsterdam Movement Sciences Vrije Universiteit Amsterdam The Netherlands
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217
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Vazquez‐Villaseñor I, Garwood CJ, Heath PR, Simpson JE, Ince PG, Wharton SB. Expression of p16 and p21 in the frontal association cortex of ALS/MND brains suggests neuronal cell cycle dysregulation and astrocyte senescence in early stages of the disease. Neuropathol Appl Neurobiol 2020; 46:171-185. [PMID: 31077599 PMCID: PMC7217199 DOI: 10.1111/nan.12559] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 05/11/2019] [Accepted: 05/08/2019] [Indexed: 12/30/2022]
Abstract
AIMS Cellular senescence plays a role in organismal ageing and has been linked to persistent DNA damage in age-related diseases. Brain senescence has been described in astrocytes and microglia, but it is less well understood in neurones. Evidence suggests that neurones activate a senescence-like mechanism that could contribute to neurodegeneration. We aimed to determine whether a persistent DNA damage response (DDR) and senescence activation are features of motor neurone disease (amyotrophic lateral sclerosis, ALS/MND). METHODS We examined expression of senescence (p16 and p21) and DNA damage markers (8-OHdG and γH2AX) in motor cortex (MCx), frontal association cortex (FACx) and occipital cortex (OCx) in post-mortem tissue donated by patients with ALS/MND and controls. RESULTS Nuclear expression of p16 and p21 was detected in glial cells; double immunofluorescence for p16/p21 and glial fibrillary acidic protein (GFAP) suggested that some of these cells were GFAP+ astrocytes. p21 nuclear expression was also found in neurones. Higher levels of p16+ (glia, P = 0.028) and p21+ (glia, P = 0.003; neurones, P = 0.008) cells were found in the FACx of ALS/MND donors but not in the MCx or OCx. Expression of p16 and p21 did not correlate with 8-OHdG or γH2AX. CONCLUSIONS Expression of p16 and p21 in glia, mainly in astrocytes, suggests senescence induction in these cells; however, neuronal p21 expression might reflect a more general mechanism of age-related cell cycle dysregulation. The significantly higher proportion of cells expressing either p16 or p21 in the FACx of ALS/MND donors could indicate senescence activation and cell cycle dysregulation in early stages of the disease.
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Affiliation(s)
- I. Vazquez‐Villaseñor
- Sheffield Institute for Translational NeuroscienceUniversity of SheffieldSheffieldUK
| | - C. J. Garwood
- Sheffield Institute for Translational NeuroscienceUniversity of SheffieldSheffieldUK
| | - P. R. Heath
- Sheffield Institute for Translational NeuroscienceUniversity of SheffieldSheffieldUK
| | - J. E. Simpson
- Sheffield Institute for Translational NeuroscienceUniversity of SheffieldSheffieldUK
| | - P. G. Ince
- Sheffield Institute for Translational NeuroscienceUniversity of SheffieldSheffieldUK
| | - S. B. Wharton
- Sheffield Institute for Translational NeuroscienceUniversity of SheffieldSheffieldUK
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218
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Selective intrarenal delivery of mesenchymal stem cell-derived extracellular vesicles attenuates myocardial injury in experimental metabolic renovascular disease. Basic Res Cardiol 2020; 115:16. [PMID: 31938859 DOI: 10.1007/s00395-019-0772-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 12/27/2019] [Indexed: 02/07/2023]
Abstract
Extracellular vesicles (EVs) deliver genes and proteins to recipient cells, and mediate paracrine actions of their parent cells. Intrarenal delivery of mesenchymal stem cell (MSC)-derived EVs preserves stenotic-kidney function and reduces release of pro-inflammatory cytokines in a swine model of coexisting metabolic syndrome (MetS) and renal artery stenosis (RAS). We hypothesized that this approach is also capable of blunting cardiac injury and dysfunction. Five groups of pigs were studied after 16 weeks of diet-induced MetS and RAS (MetS + RAS), MetS and MetS + RAS treated 4 weeks earlier with a single intrarenal delivery of EVs-rich fraction harvested from autologous adipose tissue-derived MSCs, and lean and MetS Shams. Cardiac structure, function, and myocardial oxygenation were assessed in vivo using imaging, and cardiac inflammation, senescence, and fibrosis ex vivo. Inflammatory cytokine levels were measured in circulating and renal vein blood. Intrarenal EV delivery improved stenotic-kidney glomerular filtration rate and renal blood flow, and decreased renal release of monocyte-chemoattractant protein-1 and interleukin-6. Furthermore, despite unchanged systemic hemodynamics, intrarenal EV delivery in MetS + RAS normalized cardiac diastolic function, attenuated left ventricular remodeling, cellular senescence and inflammation, and improved myocardial oxygenation and capillary density in MetS + RAS. Intrarenal delivery of MSC-derived EVs blunts myocardial injury in experimental MetS + RAS, possibly related to improvement in renal function and systemic inflammatory profile. These observations underscore the central role of inflammation in the crosstalk between the kidney and heart, and the important contribution of renal function to cardiac structural and functional integrity in coexisting MetS and RAS.
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219
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Faragher RGA, Ostler EL. Resveralogues: From Novel Ageing Mechanisms to New Therapies? Gerontology 2020; 66:231-237. [PMID: 31914446 DOI: 10.1159/000504845] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 11/18/2019] [Indexed: 11/19/2022] Open
Abstract
For much of the 20th century the ageing process was thought to be the result of the interplay of many different biological processes, each with relatively small effects on organismal lifespan. However, this model is no longer tenable. Rather it seems a few biological mechanisms, including nutrient sensing, telomere attrition and cellular senescence, mediate large effects on health and longevity. Biogerontology may have suffered from initial delusions of complexity. However, we argue that it is premature to assume either that the list of biological processes influencing lifespan is now comprehensive or that these mechanisms act independently of each other. A case in point is provided by recent work linking together changes in RNA splicing with advancing age and the ability of polyphenolics based on resveratrol to reverse replicative senescence. In this opinion piece, we propose a novel model in which the factors regulating splice restriction and those controlling cell senescence intersect across chronological and divisional time, giving rise to senescent and growing cells with more diverse properties than previously thought. We also consider therapeutic opportunities and potential problems in the light of this revised conceptual understanding of human cell senescence and ageing.
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Affiliation(s)
- Richard G A Faragher
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, United Kingdom,
| | - Elizabeth L Ostler
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, United Kingdom
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220
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Ishikawa S, Ishikawa F. Proteostasis failure and cellular senescence in long-term cultured postmitotic rat neurons. Aging Cell 2020; 19:e13071. [PMID: 31762159 PMCID: PMC6974705 DOI: 10.1111/acel.13071] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 10/05/2019] [Accepted: 10/29/2019] [Indexed: 12/31/2022] Open
Abstract
Cellular senescence, a stress-induced irreversible cell cycle arrest, has been defined for mitotic cells and is implicated in aging of replicative tissues. Age-related functional decline in the brain is often attributed to a failure of protein homeostasis (proteostasis), largely in postmitotic neurons, which accordingly is a process distinct by definition from senescence. It is nevertheless possible that proteostasis failure and cellular senescence have overlapping molecular mechanisms. Here, we identify postmitotic cellular senescence as an adaptive stress response to proteostasis failure. Primary rat hippocampal neurons in long-term cultures show molecular changes indicative of both senescence (senescence-associated β-galactosidase, p16, and loss of lamin B1) and proteostasis failure relevant to Alzheimer's disease. In addition, we demonstrate that the senescent neurons exhibit resistance to stress. Importantly, treatment of the cultures with an mTOR antagonist, protein synthesis inhibitor, or chemical compound that reduces the amount of protein aggregates relieved the proteotoxic stresses as well as the appearance of senescence markers. Our data propose mechanistic insights into the pathophysiological brain aging by establishing senescence as a primary cell-autonomous neuroprotective response.
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Affiliation(s)
- Shoma Ishikawa
- Department of Gene Mechanisms Graduate School of Biostudies Kyoto University Kyoto Japan
| | - Fuyuki Ishikawa
- Department of Gene Mechanisms Graduate School of Biostudies Kyoto University Kyoto Japan
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221
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Abstract
Aging brain becomes susceptible to neurodegenerative diseases due to the shifting of microglia and astrocyte phenotypes to an active “pro-inflammatory” state, causing chronic low-grade neuroinflammation. Despite the fact that the role of neuroinflammation during aging has been extensively studied in recent years, the underlying causes remain unclear. The identification of relevant proteins and understanding their potential roles in neuroinflammation can help explain their potential of becoming biomarkers in the aging brain and as drug targets for prevention and treatment. This will eventually reduce the chances of developing neurodegenerative diseases and promote healthier lives in the elderly. In this review, we have summarized the morphological and cellular changes in the aging brain, the effects of age-related neuroinflammation, and the potential role of cofilin-1 during neuroinflammation. We also discuss other factors contributing to brain aging and neuroinflammation.
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Affiliation(s)
- Amsha S Alsegiani
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, USA
| | - Zahoor A Shah
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, USA
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222
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Cell cycle-dependent and -independent telomere shortening accompanies murine brain aging. Aging (Albany NY) 2019; 10:3397-3420. [PMID: 30472697 PMCID: PMC6286833 DOI: 10.18632/aging.101655] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 11/15/2018] [Indexed: 12/16/2022]
Abstract
Replication-based telomere shortening during lifetime is species- and tissue-specific, however, its impact on healthy aging is unclear. In particular, the contribution of telomere truncation to the aging process of the CNS, where replicative senescence alone fails to explain organ aging due to low to absent mitotic activity of intrinsic populations, is undefined. Here, we assessed changes in relative telomere length in non-replicative and replicative neural brain populations and telomerase activity as a function of aging in C57BL/6 mice. Telomeres in neural cells and sub-selected neurons shortened with aging in a cell cycle-dependent and -independent manner, with preponderance in replicative moieties, implying that proliferation accelerates, but is not prerequisite for telomere shortening. Consistent with this telomere erosion, telomerase activity and nuclear TERT protein were not induced with aging. Knockdown of the Rela subunit of NF-κB, which controls both telomerase enzyme and subcellular TERT protein allocation, did also not influence telomerase activity or telomere length, in spite of its naive up-regulation selectively under aging conditions. We conclude that telomere instability is intrinsic to physiological brain aging beyond cell replication, and appears to occur independently of a functional interplay with NF-κB, but rather as a failure to induce or relocate telomerase.
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223
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Wengerodt D, Schmeer C, Witte OW, Kretz A. Amitosenescence and Pseudomitosenescence: Putative New Players in the Aging Process. Cells 2019; 8:cells8121546. [PMID: 31795499 PMCID: PMC6952980 DOI: 10.3390/cells8121546] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/12/2019] [Accepted: 11/27/2019] [Indexed: 12/14/2022] Open
Abstract
Replicative senescence has initially been defined as a stress reaction of replication-competent cultured cells in vitro, resulting in an ultimate cell cycle arrest at preserved growth and viability. Classically, it has been linked to critical telomere curtailment following repetitive cell divisions, and later described as a response to oncogenes and other stressors. Currently, there are compelling new directions indicating that a comparable state of cellular senescence might be adopted also by postmitotic cell entities, including terminally differentiated neurons. However, the cellular upstream inducers and molecular downstream cues mediating a senescence-like state in neurons (amitosenescence) are ill-defined. Here, we address the phenomenon of abortive atypical cell cycle activity in light of amitosenescence, and discuss why such replicative reprogramming might provide a yet unconsidered source to explain senescence in maturated neurons. We also hypothesize the existence of a G0 subphase as a priming factor for cell cycle re-entry, in analogy to discoveries in quiescent muscle stem cells. In conclusion, we propose a revision of our current view on the process and definition of senescence by encompassing a primarily replication-incompetent state (amitosenescence), which might be expanded by events of atypical cell cycle activity (pseudomitosenescence).
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Affiliation(s)
- Diane Wengerodt
- Hans-Berger Department of Neurology, Jena University Hospital, 07747 Jena, Thuringia, Germany; (D.W.); (C.S.)
| | - Christian Schmeer
- Hans-Berger Department of Neurology, Jena University Hospital, 07747 Jena, Thuringia, Germany; (D.W.); (C.S.)
- Jena Center for Healthy Ageing, Jena University Hospital, 07747 Jena, Thuringia, Germany
| | - Otto W. Witte
- Hans-Berger Department of Neurology, Jena University Hospital, 07747 Jena, Thuringia, Germany; (D.W.); (C.S.)
- Jena Center for Healthy Ageing, Jena University Hospital, 07747 Jena, Thuringia, Germany
- Correspondence: (O.W.W.); (A.K.); Tel.: +49-3641-932-3401
| | - Alexandra Kretz
- Hans-Berger Department of Neurology, Jena University Hospital, 07747 Jena, Thuringia, Germany; (D.W.); (C.S.)
- Jena Center for Healthy Ageing, Jena University Hospital, 07747 Jena, Thuringia, Germany
- Correspondence: (O.W.W.); (A.K.); Tel.: +49-3641-932-3401
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224
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Abstract
Ageing appears to be a nearly universal feature of life, ranging from unicellular microorganisms to humans. Longevity depends on the maintenance of cellular functionality, and an organism's ability to respond to stress has been linked to functional maintenance and longevity. Stress response pathways might indeed become therapeutic targets of therapies aimed at extending the healthy lifespan. Various progeroid syndromes have been linked to genome instability, indicating an important causal role of DNA damage accumulation in the ageing process and the development of age-related pathologies. Recently, non-cell-autonomous mechanisms including the systemic consequences of cellular senescence have been implicated in regulating organismal ageing. We discuss here the role of cellular and systemic mechanisms of ageing and their role in ageing-associated diseases.
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Affiliation(s)
- Paulo F L da Silva
- Institute for Genome Stability in Ageing and Disease, Medical Faculty, University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany.,Cologne Excellence Cluster for Cellular Stress Responses in Ageing-Associated Diseases (CECAD), Center for Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany
| | - Björn Schumacher
- Institute for Genome Stability in Ageing and Disease, Medical Faculty, University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany.,Cologne Excellence Cluster for Cellular Stress Responses in Ageing-Associated Diseases (CECAD), Center for Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany
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225
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Schmeer C, Kretz A, Wengerodt D, Stojiljkovic M, Witte OW. Dissecting Aging and Senescence-Current Concepts and Open Lessons. Cells 2019; 8:cells8111446. [PMID: 31731770 PMCID: PMC6912776 DOI: 10.3390/cells8111446] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/12/2019] [Accepted: 11/13/2019] [Indexed: 01/10/2023] Open
Abstract
In contrast to the programmed nature of development, it is still a matter of debate whether aging is an adaptive and regulated process, or merely a consequence arising from a stochastic accumulation of harmful events that culminate in a global state of reduced fitness, risk for disease acquisition, and death. Similarly unanswered are the questions of whether aging is reversible and can be turned into rejuvenation as well as how aging is distinguishable from and influenced by cellular senescence. With the discovery of beneficial aspects of cellular senescence and evidence of senescence being not limited to replicative cellular states, a redefinition of our comprehension of aging and senescence appears scientifically overdue. Here, we provide a factor-based comparison of current knowledge on aging and senescence, which we converge on four suggested concepts, thereby implementing the newly emerging cellular and molecular aspects of geroconversion and amitosenescence, and the signatures of a genetic state termed genosenium. We also address the possibility of an aging-associated secretory phenotype in analogy to the well-characterized senescence-associated secretory phenotype and delineate the impact of epigenetic regulation in aging and senescence. Future advances will elucidate the biological and molecular fingerprints intrinsic to either process.
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Affiliation(s)
- Christian Schmeer
- Hans-Berger Department of Neurology, Jena University Hospital, 07747 Jena, Thuringia, Germany; (A.K.); (D.W.); (M.S.); (O.W.W.)
- Jena Center for Healthy Ageing, Jena University Hospital, 07747 Jena, Thuringia, Germany
- Correspondence:
| | - Alexandra Kretz
- Hans-Berger Department of Neurology, Jena University Hospital, 07747 Jena, Thuringia, Germany; (A.K.); (D.W.); (M.S.); (O.W.W.)
- Jena Center for Healthy Ageing, Jena University Hospital, 07747 Jena, Thuringia, Germany
| | - Diane Wengerodt
- Hans-Berger Department of Neurology, Jena University Hospital, 07747 Jena, Thuringia, Germany; (A.K.); (D.W.); (M.S.); (O.W.W.)
| | - Milan Stojiljkovic
- Hans-Berger Department of Neurology, Jena University Hospital, 07747 Jena, Thuringia, Germany; (A.K.); (D.W.); (M.S.); (O.W.W.)
- Jena Center for Healthy Ageing, Jena University Hospital, 07747 Jena, Thuringia, Germany
| | - Otto W. Witte
- Hans-Berger Department of Neurology, Jena University Hospital, 07747 Jena, Thuringia, Germany; (A.K.); (D.W.); (M.S.); (O.W.W.)
- Jena Center for Healthy Ageing, Jena University Hospital, 07747 Jena, Thuringia, Germany
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226
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Targeting normal and cancer senescent cells as a strategy of senotherapy. Ageing Res Rev 2019; 55:100941. [PMID: 31408714 DOI: 10.1016/j.arr.2019.100941] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 07/04/2019] [Accepted: 08/06/2019] [Indexed: 12/19/2022]
Abstract
Senotherapy is an antiageing strategy. It refers to selective killing of senescent cells by senolytic agents, strengthening the activity of immune cells that eliminate senescent cells or alleviating the secretory phenotype (SASP) of senescent cells. As senescent cells accumulate with age and are considered to be at the root of age-related disorders, senotherapy seems to be very promising in improving healthspan. Genetic approaches, which allowed to selectively induce death of senescent cells in transgenic mice, provided proof-of-concept evidence that elimination of senescent cells can be a therapeutic approach for treating many age-related diseases. Translating these results into humans is based on searching for synthetic and natural compounds, which are able to exert such beneficial effects. The major challenge in the field is to show efficacy, safety and tolerability of senotherapy in humans. The question is how these therapeutics can influence senescence of non-dividing post-mitotic cells. Another issue concerns senescence of cancer cells induced during therapy as there is a risk of resumption of senescent cell division that could terminate in cancer renewal. Thus, development of an effective senotherapeutic strategy is also an urgent issue in cancer treatment. Different aspects, both beneficial and potentially detrimental, will be discussed in this review.
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227
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Gorgoulis V, Adams PD, Alimonti A, Bennett DC, Bischof O, Bishop C, Campisi J, Collado M, Evangelou K, Ferbeyre G, Gil J, Hara E, Krizhanovsky V, Jurk D, Maier AB, Narita M, Niedernhofer L, Passos JF, Robbins PD, Schmitt CA, Sedivy J, Vougas K, von Zglinicki T, Zhou D, Serrano M, Demaria M. Cellular Senescence: Defining a Path Forward. Cell 2019; 179:813-827. [PMID: 31675495 DOI: 10.1016/j.cell.2019.10.005] [Citation(s) in RCA: 1400] [Impact Index Per Article: 280.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 09/20/2019] [Accepted: 10/03/2019] [Indexed: 01/10/2023]
Abstract
Cellular senescence is a cell state implicated in various physiological processes and a wide spectrum of age-related diseases. Recently, interest in therapeutically targeting senescence to improve healthy aging and age-related disease, otherwise known as senotherapy, has been growing rapidly. Thus, the accurate detection of senescent cells, especially in vivo, is essential. Here, we present a consensus from the International Cell Senescence Association (ICSA), defining and discussing key cellular and molecular features of senescence and offering recommendations on how to use them as biomarkers. We also present a resource tool to facilitate the identification of genes linked with senescence, SeneQuest (available at http://Senequest.net). Lastly, we propose an algorithm to accurately assess and quantify senescence, both in cultured cells and in vivo.
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Affiliation(s)
- Vassilis Gorgoulis
- Molecular Carcinogenesis Group, Department of Histology and Embryology, Medical School, National and Kapodistrian University of Athens, Athens, Greece; Biomedical Research Foundation, Academy of Athens, Athens, Greece; Faculty Institute for Cancer Sciences, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, UK; Center for New Biotechnologies and Precision Medicine, Medical School, National and Kapodistrian University of Athens, Athens, Greece.
| | - Peter D Adams
- Institute of Cancer Sciences, University of Glasgow, Glasgow G61 1BD, UK; CRUK Beatson Institute, Glasgow G61 1BD, UK; Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Andrea Alimonti
- Institute of Oncology Research (IOR), Oncology Institute of Southern Switzerland, Bellinzona, Switzerland; Università della Svizzera Italiana, Faculty of Biomedical Sciences, Lugano, Switzerland; Department of Medicine, University of Padova, Padova, Italy; Veneto Institute of Molecular Medicine, Padova, Italy
| | - Dorothy C Bennett
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London SW17 0RE, UK
| | - Oliver Bischof
- Laboratory of Nuclear Organization and Oncogenesis, Department of Cell Biology and Infection, Inserm U993, Institute Pasteur, Paris, France
| | - Cleo Bishop
- Centre for Cell Biology and Cutaneous Research, Blizard Institute, Barts & The London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark St, London E1 2AT, UK
| | | | - Manuel Collado
- Health Research Institute of Santiago de Compostela (IDIS), Clinical University Hospital (CHUS), Santiago de Compostela, Spain
| | - Konstantinos Evangelou
- Molecular Carcinogenesis Group, Department of Histology and Embryology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Gerardo Ferbeyre
- Faculty of Medicine, Department of Biochemistry, Université de Montréal and CRCHUM, Montreal, QC, Canada
| | - Jesús Gil
- MRC London Institute of Medical Sciences (LMS), Du Cane Road, London, UK; Institute of Clinical Sciences (ICS), Faculty of Medicine, Imperial College London, Du Cane Road, London, UK
| | - Eiji Hara
- Department of Molecular Microbiology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Valery Krizhanovsky
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Diana Jurk
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN, USA
| | - Andrea B Maier
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Amsterdam Movement Sciences, Vrije Universiteit, Amsterdam, the Netherlands; Department of Medicine and Aged Care, The Royal Melbourne Hospital, The University of Melbourne, Melbourne, VIC, Australia
| | - Masashi Narita
- Cancer Research UK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
| | - Laura Niedernhofer
- Institute on the Biology of Aging and Metabolism, University of Minnesota, MN, USA
| | - João F Passos
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, MN, USA
| | - Paul D Robbins
- Institute on the Biology of Aging and Metabolism, University of Minnesota, MN, USA
| | - Clemens A Schmitt
- Charité - University Medical Center, Department of Hematology, Oncology and Tumor Immunology, Virchow Campus, and Molekulares Krebsforschungszentrum, Berlin, Germany; Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany; Kepler University Hospital, Department of Hematology and Oncology, Johannes Kepler University, Linz, Austria
| | - John Sedivy
- Department of Molecular Biology, Cell Biology and Biochemistry, and Center for the Biology of Aging, Brown University, Providence, RI, USA
| | | | - Thomas von Zglinicki
- Newcastle University Institute for Ageing, Institute for Cell and Molecular Biology, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne NE4 5PL, UK
| | - Daohong Zhou
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, USA
| | - Manuel Serrano
- Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain; Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.
| | - Marco Demaria
- University of Groningen (RUG), European Research Institute for the Biology of Aging (ERIBA), University Medical Center Groningen (UMCG), Groningen, the Netherlands.
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Hampel H, Lista S, Neri C, Vergallo A. Time for the systems-level integration of aging: Resilience enhancing strategies to prevent Alzheimer’s disease. Prog Neurobiol 2019; 181:101662. [DOI: 10.1016/j.pneurobio.2019.101662] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 06/26/2019] [Accepted: 07/14/2019] [Indexed: 01/13/2023]
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229
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Riessland M, Kolisnyk B, Kim TW, Cheng J, Ni J, Pearson JA, Park EJ, Dam K, Acehan D, Ramos-Espiritu LS, Wang W, Zhang J, Shim JW, Ciceri G, Brichta L, Studer L, Greengard P. Loss of SATB1 Induces p21-Dependent Cellular Senescence in Post-mitotic Dopaminergic Neurons. Cell Stem Cell 2019; 25:514-530.e8. [PMID: 31543366 DOI: 10.1016/j.stem.2019.08.013] [Citation(s) in RCA: 91] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 04/09/2019] [Accepted: 08/16/2019] [Indexed: 01/07/2023]
Abstract
Cellular senescence is a mechanism used by mitotic cells to prevent uncontrolled cell division. As senescent cells persist in tissues, they cause local inflammation and are harmful to surrounding cells, contributing to aging. Generally, neurodegenerative diseases, such as Parkinson's, are disorders of aging. The contribution of cellular senescence to neurodegeneration is still unclear. SATB1 is a DNA binding protein associated with Parkinson's disease. We report that SATB1 prevents cellular senescence in post-mitotic dopaminergic neurons. Loss of SATB1 causes activation of a cellular senescence transcriptional program in dopamine neurons both in human stem cell-derived dopaminergic neurons and in mice. We observed phenotypes that are central to cellular senescence in SATB1 knockout dopamine neurons in vitro and in vivo. Moreover, we found that SATB1 directly represses expression of the pro-senescence factor p21 in dopaminergic neurons. Our data implicate senescence of dopamine neurons as a contributing factor in the pathology of Parkinson's disease.
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Affiliation(s)
- Markus Riessland
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA.
| | - Benjamin Kolisnyk
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Tae Wan Kim
- Center for Stem Cell Biology, Memorial Sloan Kettering Cancer Center, 1275 York Ave., New York, NY 10065, USA; Developmental Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Ave., New York, NY 10065, USA
| | - Jia Cheng
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Jason Ni
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Jordan A Pearson
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Emily J Park
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Kevin Dam
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Devrim Acehan
- Electron Microscopy Resource Center, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Lavoisier S Ramos-Espiritu
- High-Throughput and Spectroscopy Resource Center, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Wei Wang
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Jack Zhang
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Jae-Won Shim
- Soonchunhyang Institute of Medi-bio Science (SIMS), Soonchunhyang University, Cheonan-si, Korea
| | - Gabriele Ciceri
- Center for Stem Cell Biology, Memorial Sloan Kettering Cancer Center, 1275 York Ave., New York, NY 10065, USA; Developmental Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Ave., New York, NY 10065, USA
| | - Lars Brichta
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | - Lorenz Studer
- Center for Stem Cell Biology, Memorial Sloan Kettering Cancer Center, 1275 York Ave., New York, NY 10065, USA; Developmental Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Ave., New York, NY 10065, USA.
| | - Paul Greengard
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
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Abstract
Ageing is the primary risk factor for most neurodegenerative diseases, including Alzheimer disease (AD) and Parkinson disease (PD). One in ten individuals aged ≥65 years has AD and its prevalence continues to increase with increasing age. Few or no effective treatments are available for ageing-related neurodegenerative diseases, which tend to progress in an irreversible manner and are associated with large socioeconomic and personal costs. This Review discusses the pathogenesis of AD, PD and other neurodegenerative diseases, and describes their associations with the nine biological hallmarks of ageing: genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, mitochondrial dysfunction, cellular senescence, deregulated nutrient sensing, stem cell exhaustion and altered intercellular communication. The central biological mechanisms of ageing and their potential as targets of novel therapies for neurodegenerative diseases are also discussed, with potential therapies including NAD+ precursors, mitophagy inducers and inhibitors of cellular senescence.
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231
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Moreno-Blas D, Gorostieta-Salas E, Pommer-Alba A, Muciño-Hernández G, Gerónimo-Olvera C, Maciel-Barón LA, Konigsberg M, Massieu L, Castro-Obregón S. Cortical neurons develop a senescence-like phenotype promoted by dysfunctional autophagy. Aging (Albany NY) 2019; 11:6175-6198. [PMID: 31469660 PMCID: PMC6738425 DOI: 10.18632/aging.102181] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 08/09/2019] [Indexed: 12/15/2022]
Abstract
Senescent cells accumulate in various tissues and organs with aging altering surrounding tissue due to an active secretome, and at least in mice their elimination extends healthy lifespan and ameliorates several chronic diseases. Whether all cell types senesce, including post-mitotic cells, has been poorly described mainly because cellular senescence was defined as a permanent cell cycle arrest. Nevertheless, neurons with features of senescence have been described in old rodent and human brains. In this study we characterized an in vitro model useful to study the molecular basis of senescence of primary rat cortical cells that recapitulates senescent features described in brain aging. We found that in long-term cultures, rat primary cortical neurons displayed features of cellular senescence before glial cells did, and developed a functional senescence-associated secretory phenotype able to induce paracrine premature senescence of mouse embryonic fibroblasts but proliferation of rat glial cells. Functional autophagy seems to prevent neuronal senescence, as we observed an autophagic flux reduction in senescent neurons both in vitro and in vivo, and autophagy impairment induced cortical cell senescence while autophagy stimulation inhibited it. Our findings suggest that aging-associated dysfunctional autophagy contributes to senescence transition also in neuronal cells.
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Affiliation(s)
- Daniel Moreno-Blas
- Departamento de Neurodesarrollo y Fisiología, División de Neurociencias, Instituto de Fisiología Celular, UNAM, Mexico City 04510, México
| | - Elisa Gorostieta-Salas
- Departamento de Neurodesarrollo y Fisiología, División de Neurociencias, Instituto de Fisiología Celular, UNAM, Mexico City 04510, México
| | - Alexander Pommer-Alba
- Departamento de Neurodesarrollo y Fisiología, División de Neurociencias, Instituto de Fisiología Celular, UNAM, Mexico City 04510, México
| | - Gabriel Muciño-Hernández
- Departamento de Neurodesarrollo y Fisiología, División de Neurociencias, Instituto de Fisiología Celular, UNAM, Mexico City 04510, México
| | - Cristian Gerónimo-Olvera
- Departamento de Neuropatología, División de Neurociencias, Instituto de Fisiología Celular, UNAM, Mexico City 04510, México
| | - Luis Angel Maciel-Barón
- Departamento de Ciencias de la Salud, Universidad Autónoma Metropolitana, Unidad Iztapalapa, Mexico City 09340, México
| | - Mina Konigsberg
- Departamento de Ciencias de la Salud, Universidad Autónoma Metropolitana, Unidad Iztapalapa, Mexico City 09340, México
| | - Lourdes Massieu
- Departamento de Neuropatología, División de Neurociencias, Instituto de Fisiología Celular, UNAM, Mexico City 04510, México
| | - Susana Castro-Obregón
- Departamento de Neurodesarrollo y Fisiología, División de Neurociencias, Instituto de Fisiología Celular, UNAM, Mexico City 04510, México
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232
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Granzotto A, Bomba M, Castelli V, Navarra R, Massetti N, d'Aurora M, Onofrj M, Cicalini I, Del Boccio P, Gatta V, Cimini A, Piomelli D, Sensi SL. Inhibition of de novo ceramide biosynthesis affects aging phenotype in an in vitro model of neuronal senescence. Aging (Albany NY) 2019; 11:6336-6357. [PMID: 31467258 PMCID: PMC6738398 DOI: 10.18632/aging.102191] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 08/10/2019] [Indexed: 12/13/2022]
Abstract
Although aging is considered to be an unavoidable event, recent experimental evidence suggests that the process can be counteracted. Intracellular calcium (Ca2+i) dyshomeostasis, mitochondrial dysfunction, oxidative stress, and lipid dysregulation are critical factors that contribute to senescence-related processes. Ceramides, a pleiotropic class of sphingolipids, are important mediators of cellular senescence, but their role in neuronal aging is still largely unexplored. In this study, we investigated the effects of L-cycloserine (L-CS), an inhibitor of thede novoceramide biosynthesis, on the aging phenotype of cortical neurons cultured for 22 days, a setting employed as anin vitromodel of senescence. Our findings indicate that, compared to control cultures, ‘aged’ neurons display dysregulation of [Ca2+]ilevels, mitochondrial dysfunction, increased generation of reactive oxygen species (ROS), altered synaptic activity as well as the activation of neuronal death-related molecules. Treatment with L-CS positively affected the senescent phenotype, a result associated with recovery of neuronal [Ca2+]isignaling and reduction of mitochondrial dysfunction and ROS generation. The results suggest that thede novoceramide biosynthesis represents a critical intermediate in the molecular and functional cascade leading to neuronal senescence and identify ceramide biosynthesis inhibitors as promising pharmacological tools to decrease age-related neuronal dysfunctions.
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Affiliation(s)
- Alberto Granzotto
- Center of Excellence on Aging and Translational Medicine (CeSI-MeT), University G. d'Annunzio of Chieti-Pescara, Chieti, Italy.,Department of Neuroscience, Imaging, and Clinical Sciences, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Manuela Bomba
- Center of Excellence on Aging and Translational Medicine (CeSI-MeT), University G. d'Annunzio of Chieti-Pescara, Chieti, Italy.,Department of Neuroscience, Imaging, and Clinical Sciences, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Vanessa Castelli
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Riccardo Navarra
- Department of Neuroscience, Imaging, and Clinical Sciences, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Noemi Massetti
- Center of Excellence on Aging and Translational Medicine (CeSI-MeT), University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Marco d'Aurora
- Center of Excellence on Aging and Translational Medicine (CeSI-MeT), University G. d'Annunzio of Chieti-Pescara, Chieti, Italy.,Department of Psychological, Health and Territorial Sciences, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Marco Onofrj
- Center of Excellence on Aging and Translational Medicine (CeSI-MeT), University G. d'Annunzio of Chieti-Pescara, Chieti, Italy.,Department of Neuroscience, Imaging, and Clinical Sciences, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Ilaria Cicalini
- Center of Excellence on Aging and Translational Medicine (CeSI-MeT), University G. d'Annunzio of Chieti-Pescara, Chieti, Italy.,Department of Pharmacy, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Piero Del Boccio
- Center of Excellence on Aging and Translational Medicine (CeSI-MeT), University G. d'Annunzio of Chieti-Pescara, Chieti, Italy.,Department of Pharmacy, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Valentina Gatta
- Center of Excellence on Aging and Translational Medicine (CeSI-MeT), University G. d'Annunzio of Chieti-Pescara, Chieti, Italy.,Department of Psychological, Health and Territorial Sciences, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Annamaria Cimini
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy.,Sbarro Institute for Cancer Research and Molecular Medicine and Center for Biotechnology, Temple University, Philadelphia, PA 19122, USA.,National Institute for Nuclear Physics (INFN), Gran Sasso National Laboratory (LNGS), Assergi, Italy
| | - Daniele Piomelli
- Departments of Anatomy and Neurobiology, Biochemistry and Pharmacology, University of California Irvine, Irvine, CA 92697, USA
| | - Stefano L Sensi
- Center of Excellence on Aging and Translational Medicine (CeSI-MeT), University G. d'Annunzio of Chieti-Pescara, Chieti, Italy.,Department of Neuroscience, Imaging, and Clinical Sciences, University G. d'Annunzio of Chieti-Pescara, Chieti, Italy.,Departments of Neurology and Pharmacology, Institute for Mind Impairments and Neurological Disorders (iMIND), University of California Irvine, Irvine, CA 92697, USA
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233
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Guo Z, Tian Y, Guo Y, Li B, Liu X, Xie K, Song Y, Wang D. RAD6B Plays a Critical Role in Neuronal DNA Damage Response to Resist Neurodegeneration. Front Cell Neurosci 2019; 13:392. [PMID: 31507381 PMCID: PMC6716356 DOI: 10.3389/fncel.2019.00392] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 08/09/2019] [Indexed: 01/31/2023] Open
Abstract
RAD6 participates in DNA double-strand breaks (DSBs) repair by ubiquitinating histone H2B in mitotic cells. In terminally differentiated cells, however, the mechanisms of DNA damage repair are less well known. In this study, we investigate whether RAD6B is involved in DSBs repair in neurons and effects of RAD6B deficiency on neuronal survival. We compared neurons of RAD6B-deficient mice with those of littermate wild type (WT) mice and induced DNA damage by X-ray irradiation. We provide evidence that RAD6B is essential for neural DDR and RAD6B deficiency results in increased genomic instability and neurodegeneration. Moreover, higher levels of p53 and p21 are present in the brains of RAD6B-deficient mice, which may be responsible for neuronal senescence, and degeneration. In addition, behavioral experiments show that RAD6B-deficient mice exhibit marked learning and memory deficits. In conclusion, these findings suggest that RAD6B is critical for neural integrity and that the absence of RAD6B accelerates neurodegeneration in mice.
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Affiliation(s)
- Zhao Guo
- Department of Anatomy and Histology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China
| | - Yingxia Tian
- Department of Internal Medicine, Gansu Provincial Academic Institute for Medical Research, Lanzhou, China
| | - Yingli Guo
- Department of Anatomy and Histology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China
| | - Boya Li
- Department of Anatomy and Histology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China
| | - Xiangwen Liu
- Department of Anatomy and Histology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China
| | - Kun Xie
- Department of Anatomy and Histology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China
| | - Yanfeng Song
- Department of Anatomy and Histology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China
| | - Degui Wang
- Department of Anatomy and Histology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China
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234
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Yousefzadeh MJ, Melos KI, Angelini L, Burd CE, Robbins PD, Niedernhofer LJ. Mouse Models of Accelerated Cellular Senescence. Methods Mol Biol 2019; 1896:203-230. [PMID: 30474850 DOI: 10.1007/978-1-4939-8931-7_17] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Senescent cells accumulate in multiple tissues as virtually all vertebrate organisms age. Senescence is a highly conserved response to many forms of cellular stress intended to block the propagation of damaged cells. Senescent cells have been demonstrated to play a causal role in aging via their senescence-associated secretory phenotype and by impeding tissue regeneration. Depletion of senescent cells either through genetic or pharmacologic methods has been demonstrated to extend murine lifespan and delay the onset of age-related diseases. Measuring the burden and location of senescent cells in vivo remains challenging, as there is no marker unique to senescent cells. Here, we describe multiple methods to detect the presence and extent of cellular senescence in preclinical models, with a special emphasis on murine models of accelerated aging that exhibit a more rapid onset of cellular senescence.
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Affiliation(s)
- Matthew J Yousefzadeh
- Institute on the Biology of Aging and Metabolism, University of Minnesota, Minneapolis, MN, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, USA
| | - Kendra I Melos
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, USA
| | - Luise Angelini
- Institute on the Biology of Aging and Metabolism, University of Minnesota, Minneapolis, MN, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, USA
| | - Christin E Burd
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
| | - Paul D Robbins
- Institute on the Biology of Aging and Metabolism, University of Minnesota, Minneapolis, MN, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, USA
| | - Laura J Niedernhofer
- Institute on the Biology of Aging and Metabolism, University of Minnesota, Minneapolis, MN, USA.
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235
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New Insights into Chronological Mobility of Retrotransposons In Vivo. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:2818415. [PMID: 31346359 PMCID: PMC6617872 DOI: 10.1155/2019/2818415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 06/03/2019] [Indexed: 12/17/2022]
Abstract
Tissue aging is the gradual decline of physiological homeostasis accompanied with accumulation of senescent cells, decreased clearance of unwanted biological compounds, and depletion of stem cells. Senescent cells were cell cycle arrested in response to various stimuli and identified using distinct phenotypes and changes in gene expression. Senescent cells that accumulate with aging can compromise normal tissue function and inhibit or stop repair and regeneration. Selective removal of senescent cells can slow the aging process and inhibits age-associated diseases leading to extended lifespans in mice and thus provides a possibility for developing antiaging therapy. To monitor the appearance of senescent cells in vivo and target them, a clearer understanding of senescent cell expression markers is needed. We investigated the age-associated expression of three molecular hallmarks of aging: SA-β-gal, P16INK4a, and retrotransposable elements (RTEs), in different mouse tissues during chronological aging. Our data showed that the expression of these markers is variable with aging in the different tissues. P16INK4a showed consistent increases with age in most tissues, while expression of RTEs was variable among different tissues examined. These data suggest that biological changes occurring with physiological aging may be useful in choosing the appropriate timing of therapeutic interventions to slow the aging process or keep more susceptible organs healthier in the aging process.
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236
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Ogrodnik M, Salmonowicz H, Jurk D, Passos JF. Expansion and Cell-Cycle Arrest: Common Denominators of Cellular Senescence. Trends Biochem Sci 2019; 44:996-1008. [PMID: 31345557 DOI: 10.1016/j.tibs.2019.06.011] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 06/24/2019] [Accepted: 06/26/2019] [Indexed: 12/21/2022]
Abstract
Cellular senescence is a major driver of age-related diseases, and senotherapies are being tested in clinical trials. Despite its popularity, cellular senescence is weakly defined and is frequently referred to as irreversible cell-cycle arrest. In this article we hypothesize that cellular senescence is a phenotype that results from the coordination of two processes: cell expansion and cell-cycle arrest. We provide evidence for the compatibility of the proposed model with recent findings showing senescence in postmitotic tissues, wound healing, obesity, and development. We believe our model also explains why some characteristics of senescence can be found in non-senescent cells. Finally, we propose new avenues for research from our model.
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Affiliation(s)
- Mikolaj Ogrodnik
- Department of Physiology and Biochemical Engineering, Mayo Clinic, Rochester, MN, USA.
| | - Hanna Salmonowicz
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | - Diana Jurk
- Department of Physiology and Biochemical Engineering, Mayo Clinic, Rochester, MN, USA; Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | - João F Passos
- Department of Physiology and Biochemical Engineering, Mayo Clinic, Rochester, MN, USA; Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK.
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237
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de Mera-Rodríguez JA, Álvarez-Hernán G, Gañán Y, Martín-Partido G, Rodríguez-León J, Francisco-Morcillo J. Senescence-associated β-galactosidase activity in the developing avian retina. Dev Dyn 2019; 248:850-865. [PMID: 31226225 DOI: 10.1002/dvdy.74] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 05/22/2019] [Accepted: 06/15/2019] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Senescence-associated β-galactosidase (SA-β-GAL) histochemistry is the most commonly used biomarker of cellular senescence. These SA-β-GAL-positive cells are senescent embryonic cells that are usually removed by apoptosis from the embryo, followed by macrophage-mediated clearance. RESULTS Some authors have proposed that SA-β-GAL activity in differentiated neurons from young and adult mammals cannot be uniquely attributed to cell senescence, whether in vivo or in vitro. Using the developing visual system of the chicken as a model, the present study found that SA-β-GAL detected in the developing retina corresponded to lysosomal β-galactosidase activity, and that SA-β-GAL activity did not correlate with the chronotopographical distribution of apoptotic cells. However, SA-β-GAL staining in the undifferentiated retina coincided with the appearance of early differentiating neurons. In the laminated retina, SA-β-GAL staining was concentrated in the ganglion, amacrine, and horizontal cell layers. The photoreceptors and pigment epithelial cells also exhibited SA-β-GAL activity throughout retinal development. We have also found that SA-β-GAL staining strongly correlated p21 immunoreactivity. CONCLUSION In conclusion, the results clearly show that SA-β-GAL activity cannot be regarded as a specific marker of senescence during retinal development, and that it is mainly expressed in subpopulations of postmitotic neurons, which are nonproliferative cells, even at early stages of cell differentiation.
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Affiliation(s)
- José Antonio de Mera-Rodríguez
- Área de Anatomía Humana, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Medicina, Universidad de Extremadura, Badajoz, Spain
| | - Guadalupe Álvarez-Hernán
- Área de Biología Celular, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Yolanda Gañán
- Área de Anatomía Humana, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Medicina, Universidad de Extremadura, Badajoz, Spain
| | - Gervasio Martín-Partido
- Área de Biología Celular, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Joaquín Rodríguez-León
- Área de Anatomía Humana, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Medicina, Universidad de Extremadura, Badajoz, Spain
| | - Javier Francisco-Morcillo
- Área de Biología Celular, Departamento de Anatomía, Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
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Vascular smooth muscle cell senescence and age-related diseases: State of the art. Biochim Biophys Acta Mol Basis Dis 2019; 1865:1810-1821. [DOI: 10.1016/j.bbadis.2018.08.015] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 07/20/2018] [Accepted: 08/13/2018] [Indexed: 02/07/2023]
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239
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Osorio C, Kanukuntla T, Diaz E, Jafri N, Cummings M, Sfera A. The Post-amyloid Era in Alzheimer's Disease: Trust Your Gut Feeling. Front Aging Neurosci 2019; 11:143. [PMID: 31297054 PMCID: PMC6608545 DOI: 10.3389/fnagi.2019.00143] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 05/29/2019] [Indexed: 12/14/2022] Open
Abstract
The amyloid hypothesis, the assumption that beta-amyloid toxicity is the primary cause of neuronal and synaptic loss, has been the mainstream research concept in Alzheimer's disease for the past two decades. Currently, this model is quietly being replaced by a more holistic, “systemic disease” paradigm which, like the aging process, affects multiple body tissues and organs, including the gut microbiota. It is well-established that inflammation is a hallmark of cellular senescence; however, the infection-senescence link has been less explored. Microbiota-induced senescence is a gradually emerging concept promoted by the discovery of pathogens and their products in Alzheimer's disease brains associated with senescent neurons, glia, and endothelial cells. Infectious agents have previously been associated with Alzheimer's disease, but the cause vs. effect issue could not be resolved. A recent study may have settled this debate as it shows that gingipain, a Porphyromonas gingivalis toxin, can be detected not only in Alzheimer's disease but also in the brains of older individuals deceased prior to developing the illness. In this review, we take the position that gut and other microbes from the body periphery reach the brain by triggering intestinal and blood-brain barrier senescence and disruption. We also surmise that novel Alzheimer's disease findings, including neuronal somatic mosaicism, iron dyshomeostasis, aggressive glial phenotypes, and loss of aerobic glycolysis, can be explained by the infection-senescence model. In addition, we discuss potential cellular senescence targets and therapeutic strategies, including iron chelators, inflammasome inhibitors, senolytic antibiotics, mitophagy inducers, and epigenetic metabolic reprograming.
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Affiliation(s)
- Carolina Osorio
- Psychiatry, Loma Linda University, Loma Linda, CA, United States
| | - Tulasi Kanukuntla
- Department of Psychiatry, Patton State Hospital, San Bernardino, CA, United States
| | - Eddie Diaz
- Department of Psychiatry, Patton State Hospital, San Bernardino, CA, United States
| | - Nyla Jafri
- Department of Psychiatry, Patton State Hospital, San Bernardino, CA, United States
| | - Michael Cummings
- Department of Psychiatry, Patton State Hospital, San Bernardino, CA, United States
| | - Adonis Sfera
- Department of Psychiatry, Patton State Hospital, San Bernardino, CA, United States
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240
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Abstract
Replicative capacity of somatic cells is limited. It indicates that aging also develops at the cellular level, and this is described as "cellular senescence". Senescent cells become flattened, enlarged, and irreversibly lose capacity for proliferation. Lack of specific and conclusive markers for cellular senescence makes it difficult to comprehensively define and understand this biological process especially in vivo. Molecules including p53, p21, p16Ink4a, p38MAPK, and γH2AX, telomere attrition, enhanced signals for SA-β-gal, etc. are widely used to detect senescent cells, but these are indirect indicators of cellular senescence, and biological markers reflecting direct evidence need to be established. Genetic profiles are altered in senescent cells, letting these cells secrete pro-inflammatory molecules. Aging or age-related disorders including heart failure and atherosclerotic diseases link with an accumulation of cells undergoing cellular senescence in cardiovascular systems including heart and vessels. Senescent cells become pathogenic in most cases by mediating chronic sterile inflammation and tissue remodeling. A recent conceptual as well as technical breakthrough in this research area is "senolysis", meaning the specific elimination of senescent cells. Genetic as well as pharmacological models with senolysis contributed to reverse aging phenotypes and ameliorated pathologies in age-related disorders without enhancing the risk of tumorigenesis, and opened a new avenue for aging research. Several compounds are identified as senolytics, and some are already tested in clinical settings. It was recently reported that senolysis reverses aging phenotype in cardiovascular disorders. Generating therapies targeting suppression or elimination of senescent cells would inhibit the progression of undesirable aspects of aging, and become promising therapies for cardiac diseases.
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Affiliation(s)
- Ippei Shimizu
- Department of Cardiovascular Biology and Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan; Division of Molecular Aging and Cell Biology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
| | - Tohru Minamino
- Department of Cardiovascular Biology and Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
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241
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Huff WX, Kwon JH, Henriquez M, Fetcko K, Dey M. The Evolving Role of CD8 +CD28 - Immunosenescent T Cells in Cancer Immunology. Int J Mol Sci 2019; 20:ijms20112810. [PMID: 31181772 PMCID: PMC6600236 DOI: 10.3390/ijms20112810] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/05/2019] [Accepted: 06/06/2019] [Indexed: 12/18/2022] Open
Abstract
Functional, tumor-specific CD8+ cytotoxic T lymphocytes drive the adaptive immune response to cancer. Thus, induction of their activity is the ultimate aim of all immunotherapies. Success of anti-tumor immunotherapy is precluded by marked immunosuppression in the tumor microenvironment (TME) leading to CD8+ effector T cell dysfunction. Among the many facets of CD8+ T cell dysfunction that have been recognized—tolerance, anergy, exhaustion, and senescence—CD8+ T cell senescence is incompletely understood. Naïve CD8+ T cells require three essential signals for activation, differentiation, and survival through T-cell receptor, costimulatory receptors, and cytokine receptors. Downregulation of costimulatory molecule CD28 is a hallmark of senescent T cells and increased CD8+CD28− senescent populations with heterogeneous roles have been observed in multiple solid and hematogenous tumors. T cell senescence can be induced by several factors including aging, telomere damage, tumor-associated stress, and regulatory T (Treg) cells. Tumor-induced T cell senescence is yet another mechanism that enables tumor cell resistance to immunotherapy. In this paper, we provide a comprehensive overview of CD8+CD28− senescent T cell population, their origin, their function in immunology and pathologic conditions, including TME and their implication for immunotherapy. Further characterization and investigation into this subset of CD8+ T cells could improve the efficacy of future anti-tumor immunotherapy.
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Affiliation(s)
- Wei X Huff
- Department of Neurosurgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
| | - Jae Hyun Kwon
- Department of Neurosurgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
| | - Mario Henriquez
- Department of Neurosurgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
| | - Kaleigh Fetcko
- Department of Neurology, University of Illinois at Chicago School of Medicine, Chicago, IL 60612, USA.
| | - Mahua Dey
- Department of Neurosurgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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242
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Abstract
Telomeres are specialised structures at the end of linear chromosomes. They consist of tandem repeats of the hexanucleotide sequence TTAGGG, as well as a protein complex called shelterin. Together, they form a protective loop structure against chromosome fusion and degradation. Shortening or damage to telomeres and opening of the loop induce an uncapped state that triggers a DNA damage response resulting in senescence or apoptosis.Average telomere length, usually measured in human blood lymphocytes, was thought to be a biomarker for ageing, survival and mortality. However, it becomes obvious that regulation of telomere length is very complex and involves multiple processes. For example, the "end replication problem" during DNA replication as well as oxidative stress are responsible for the shortening of telomeres. In contrast, telomerase activity can potentially counteract telomere shortening when it is able to access and interact with telomeres. However, while highly active during development and in cancer cells, the enzyme is down-regulated in most human somatic cells with a few exceptions such as human lymphocytes. In addition, telomeres can be transcribed, and the transcription products called TERRA are involved in telomere length regulation.Thus, telomere length and their integrity are regulated at many different levels, and we only start to understand this process under conditions of increased oxidative stress, inflammation and during diseases as well as the ageing process.This chapter aims to describe our current state of knowledge on telomeres and telomerase and their regulation in order to better understand their role for the ageing process.
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243
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Cohen J, Torres C. Astrocyte senescence: Evidence and significance. Aging Cell 2019; 18:e12937. [PMID: 30815970 PMCID: PMC6516680 DOI: 10.1111/acel.12937] [Citation(s) in RCA: 141] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 01/14/2019] [Accepted: 02/04/2019] [Indexed: 12/12/2022] Open
Abstract
Astrocytes participate in numerous aspects of central nervous system (CNS) physiology ranging from ion balance to metabolism, and disruption of their physiological roles can therefore be a contributor to CNS dysfunction and pathology. Cellular senescence, one of the mechanisms of aging, has been proposed as a central component of the age dependency of neurodegenerative disorders. Cumulative evidence supports an integral role of astrocytes in the initiation and progression of neurodegenerative disease and cognitive decline with aging. The loss of astrocyte function or the gain of neuroinflammatory function as a result of cellular senescence could have profound implications for the aging brain and neurodegenerative disorders, and we propose the term “astrosenescence” to describe this phenotype. This review summarizes the current evidence pertaining to astrocyte senescence from early evidence, in vitro characterization and relationship to age‐related neurodegenerative disease. We discuss the significance of targeting senescent astrocytes as a novel approach toward therapies for age‐associated neurodegenerative disease.
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Affiliation(s)
- Justin Cohen
- Department of Pathology and Laboratory Medicine Drexel University College of Medicine Philadelphia Pennsylvania
| | - Claudio Torres
- Department of Pathology and Laboratory Medicine Drexel University College of Medicine Philadelphia Pennsylvania
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244
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Chromosomal instability and pro-inflammatory response in aging. Mech Ageing Dev 2019; 182:111118. [PMID: 31102604 DOI: 10.1016/j.mad.2019.111118] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 04/25/2019] [Accepted: 05/14/2019] [Indexed: 01/10/2023]
Abstract
Aging refers to the progressive deterioration of tissue and organ function over time. Increasing evidence points to the accumulation of highly damaged cell cycle-arrested cells with age (cellular senescence) as major reason for the development of certain aging-associated diseases. Recent studies have independently shown that aneuploidy, an abnormal chromosome set, occurs in senescent cells, and that the accumulation of cytoplasmic DNA driven by faulty chromosome segregation during mitosis aids in the establishment of senescence and its associated secretory phenotype known as SASP. Here we review the emerging link between chromosomal instability (CIN) and senescence in the context of aging, with emphasis on the cGAS-STING pathway activation and its role in the development of the SASP. Based on current evidence, we propose that age-associated CIN in mitotically active cells contributes to aging and its associated diseases, and we discuss the inhibition of CIN as a potential strategy to prevent the generation of aneuploid senescent cells and thereby to delay aging.
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245
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Ogrodnik M, Zhu Y, Langhi LGP, Tchkonia T, Krüger P, Fielder E, Victorelli S, Ruswhandi RA, Giorgadze N, Pirtskhalava T, Podgorni O, Enikolopov G, Johnson KO, Xu M, Inman C, Palmer AK, Schafer M, Weigl M, Ikeno Y, Burns TC, Passos JF, von Zglinicki T, Kirkland JL, Jurk D. Obesity-Induced Cellular Senescence Drives Anxiety and Impairs Neurogenesis. Cell Metab 2019; 29:1061-1077.e8. [PMID: 30612898 PMCID: PMC6509403 DOI: 10.1016/j.cmet.2018.12.008] [Citation(s) in RCA: 251] [Impact Index Per Article: 50.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 10/23/2018] [Accepted: 12/05/2018] [Indexed: 12/25/2022]
Abstract
Cellular senescence entails a stable cell-cycle arrest and a pro-inflammatory secretory phenotype, which contributes to aging and age-related diseases. Obesity is associated with increased senescent cell burden and neuropsychiatric disorders, including anxiety and depression. To investigate the role of senescence in obesity-related neuropsychiatric dysfunction, we used the INK-ATTAC mouse model, from which p16Ink4a-expressing senescent cells can be eliminated, and senolytic drugs dasatinib and quercetin. We found that obesity results in the accumulation of senescent glial cells in proximity to the lateral ventricle, a region in which adult neurogenesis occurs. Furthermore, senescent glial cells exhibit excessive fat deposits, a phenotype we termed "accumulation of lipids in senescence." Clearing senescent cells from high fat-fed or leptin receptor-deficient obese mice restored neurogenesis and alleviated anxiety-related behavior. Our study provides proof-of-concept evidence that senescent cells are major contributors to obesity-induced anxiety and that senolytics are a potential new therapeutic avenue for treating neuropsychiatric disorders.
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Affiliation(s)
- Mikolaj Ogrodnik
- Institute for Cell and Molecular Biosciences, Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK; Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Yi Zhu
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Larissa G P Langhi
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Tamar Tchkonia
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Patrick Krüger
- Institute for Cell and Molecular Biosciences, Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK
| | - Edward Fielder
- Institute for Cell and Molecular Biosciences, Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK
| | - Stella Victorelli
- Institute for Cell and Molecular Biosciences, Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK
| | - Rifqha A Ruswhandi
- Institute for Cell and Molecular Biosciences, Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK
| | - Nino Giorgadze
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Tamar Pirtskhalava
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Oleg Podgorni
- Department of Anesthesiology, Stony Brook School of Medicine, 101 Nicolls Road, Stony Brook, New York, NY 11794, USA; Center for Developmental Genetics, Stony Brook University, 100 Nicolls Road, Stony Brook, New York, NY 11794, USA
| | - Grigori Enikolopov
- Department of Anesthesiology, Stony Brook School of Medicine, 101 Nicolls Road, Stony Brook, New York, NY 11794, USA; Center for Developmental Genetics, Stony Brook University, 100 Nicolls Road, Stony Brook, New York, NY 11794, USA; Department of Nano-, Bio-, Information Technology and Cognitive Science, Moscow Institute of Physics and Technology, Moscow, Russia; Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, NY, USA
| | - Kurt O Johnson
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Ming Xu
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Christine Inman
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Allyson K Palmer
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Marissa Schafer
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Moritz Weigl
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Yuji Ikeno
- The Barshop Institute for Longevity and Aging Studies, San Antonio, Department of Pathology, The University of Texas Health Science Center at San Antonio, Research Service, Audie L. Murphy VA Hospital (STVHCS), San Antonio, TX 78229, USA
| | - Terry C Burns
- Departments of Neurologic Surgery and Neuroscience, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - João F Passos
- Institute for Cell and Molecular Biosciences, Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN 55905, USA
| | - Thomas von Zglinicki
- Institute for Cell and Molecular Biosciences, Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK; Near East University, Arts and Sciences Faculty, Molecular Biology and Genetics, Nicosia, North Cyprus POB 99138 Mersin 10, Turkey
| | - James L Kirkland
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
| | - Diana Jurk
- Institute for Cell and Molecular Biosciences, Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK; Robert and Arlene Kogod Center on Aging, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN 55905, USA.
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246
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Walton CC, Andersen JK. Unknown fates of (brain) oxidation or UFO: Close encounters with neuronal senescence. Free Radic Biol Med 2019; 134:695-701. [PMID: 30639615 DOI: 10.1016/j.freeradbiomed.2019.01.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 01/08/2019] [Accepted: 01/08/2019] [Indexed: 11/19/2022]
Abstract
Oxidative stress has long been considered a key component contributing to pathologies associated with brain aging and age-related neurodegenerative diseases. The proposed mechanisms involved are varied, but recently have been suggested to include induction of cellular senescence, a cellular growth arrest state characterized by the secretion of pre-inflammatory senescence-associated secretory phenotype (SASP) factors. The post-mitotic status of neurons has been traditionally considered to prohibit cellular senescence, however recent studies have provided compelling evidence that neurons may be capable of undergoing senescence in response to oxidative stress and other factors. Development of senolytics, small molecules that selectively induce senescent cell death, could represent a paradigm change for the treatment of neurodegenerative diseases including Alzheimer's and Parkinson's disease (AD, PD). However, their use depends on unequivocal validation that neurons can senesce and that they do not have detrimental off-target effects in other cell types in the brain and elsewhere.
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247
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Abstract
Cellular senescence refers to a process induced by various types of stress that causes irreversible cell cycle arrest and distinct cellular alterations, including profound changes in gene expression, metabolism, and chromatin organization as well as activation/reinforcement of anti-apoptotic pathways and development of a pro-inflammatory secretome or senescence-associated secretory phenotype (SASP). However, because of challenges and technical limitations in identifying and characterizing senescent cells in living organisms, only recently have some of the diverse in vivo roles of these unique cells been discovered. New findings indicate that senescent cells and their SASP can have acute beneficial functions, such as in tissue regeneration and wound healing. However, in contrast, when senescent cells accumulate in excess chronically at sites of pathology or in old tissues they drive multiple age-associated chronic diseases. Senotherapeutics that selectively eliminate senescent cells ("senolytics") or inhibit their detrimental SASP ("senomorphics") have been developed and tested in aged preclinical models. These studies have established that targeting senescence is a powerful anti-aging strategy to improve "healthspan" - i.e., the healthy period of life free of chronic disease. The roles of senescence in mediating age-related bone loss have been a recent focus of rigorous investigation. Studies in mice and humans demonstrate that with aging, at least a subset of most cell types in the bone microenvironment become senescent and develop a heterogeneous SASP. Furthermore, age-related bone loss can be alleviated in old mice, with apparent advantages over anti-resorptive therapy, by reducing the senescent cell burden genetically or pharmacologically with the first class of senolytics or a senomorphic. Collectively, these findings point to targeting senescence as a transformational strategy to extend healthspan, therefore providing strong rationale for identifying and optimizing senotherapeutics to alleviate multiple chronic diseases of aging, including osteoporosis, and set the stage for translating senotherapeutics to humans, with clinical trials currently ongoing.
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Affiliation(s)
- Joshua N Farr
- Division of Endocrinology and Metabolism and Kogod Center on Aging, Mayo Clinic, Rochester, MN, USA.
| | - Sundeep Khosla
- Division of Endocrinology and Metabolism and Kogod Center on Aging, Mayo Clinic, Rochester, MN, USA.
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248
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Keefe DL. Telomeres and genomic instability during early development. Eur J Med Genet 2019; 63:103638. [PMID: 30862510 DOI: 10.1016/j.ejmg.2019.03.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 03/05/2019] [Indexed: 12/21/2022]
Abstract
Genomic instability is widespread during early embryo development. Aneuploidy, mosaicism, and copy number variants (CNVs) commonly appear in human preimplantation embryos. Both age-dependent meiotic aneuploidy and age-independent mitotic aneuploidy and CNVs occur In human embryos. Telomere attrition, which contributes to genomic instability in somatic cells, also may promote genomic instability in preimplantation embryos. Telomere dynamics during gametogenesis are strikingly dimorphic between females and males. Sperm telomeres lengthen with advancing paternal age, while oocyte telomeres are among the shortest in the body. Spermatogonia express telomerase activity throughout the life of the male, while oocytes and cleavage stage embryos express low or un-measureable levels of telomerase activity. Telomere attrition in oocytes contributes to meiotic dysfunction, including spindle dysmorphologies, reduced synapsis and chiasmata, as well as delayed, arrested and fragmented embryos. Cleavage stage embryos, with such inefficient telomere reconstitution, likely undergo NHEJ, which produces anaphase lag, chromosome bridges, micronuclei, and genomic instability, including mosaicism and CNVs. Cleavage stage embryos reconstitute the short telomeres inherited from their mothers by Alternative Lengthening of Telomeres (ALT), a DNA recombination based method involving RAD 50, MRE 11, Werner and Bloom proteins, as well as telomere sister chromatid exchange. ALT robustly reconstitutes telomeres, but also predisposes to genomic instability.
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Affiliation(s)
- David L Keefe
- Department of Ob/Gyn, NYU Langone Medical Center, 550 First Avenue, NBV 9N1A, New York, 10012, New York, USA.
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249
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Neuronal AMP-activated protein kinase hyper-activation induces synaptic loss by an autophagy-mediated process. Cell Death Dis 2019; 10:221. [PMID: 30833547 PMCID: PMC6399353 DOI: 10.1038/s41419-019-1464-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 01/29/2019] [Accepted: 02/14/2019] [Indexed: 02/01/2023]
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by synaptic loss that leads to the development of cognitive deficits. Synapses are neuronal structures that play a crucial role in memory formation and are known to consume most of the energy used in the brain. Interestingly, AMP-activated protein kinase (AMPK), the main intracellular energy sensor, is hyper-activated in degenerating neurons in several neurodegenerative diseases, including AD. In this context, we asked whether AMPK hyper-activation could influence synapses' integrity and function. AMPK hyper-activation in differentiated primary neurons led to a time-dependent decrease in pre- and post-synaptic markers, which was accompanied by a reduction in synapses number and a loss of neuronal networks functionality. The loss of post-synaptic proteins was mediated by an AMPK-regulated autophagy-dependent pathway. Finally, this process was also observed in vivo, where AMPK hyper-activation primed synaptic loss. Overall, our data demonstrate that during energetic stress condition, AMPK might play a fundamental role in the maintenance of synaptic integrity, at least in part through the regulation of autophagy. Thus, AMPK might represent a potential link between energetic failure and synaptic integrity in neurodegenerative conditions such as AD.
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250
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Short S, Fielder E, Miwa S, von Zglinicki T. Senolytics and senostatics as adjuvant tumour therapy. EBioMedicine 2019; 41:683-692. [PMID: 30737084 PMCID: PMC6441870 DOI: 10.1016/j.ebiom.2019.01.056] [Citation(s) in RCA: 124] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/16/2019] [Accepted: 01/30/2019] [Indexed: 12/25/2022] Open
Abstract
Cell senescence is a driver of ageing, frailty, age-associated disease and functional decline. In oncology, tumour cell senescence may contribute to the effect of adjuvant therapies, as it blocks tumour growth. However, this is frequently incomplete, and tumour cells that recover from senescence may gain a more stem-like state with increased proliferative potential. This might be exaggerated by the induction of senescence in the surrounding niche cells. Finally, senescence will spread through bystander effects, possibly overwhelming the capacity of the immune system to ablate senescent cells. This induces a persistent system-wide senescent cell accumulation, which we hypothesize is the cause for the premature frailty, multi-morbidity and increased mortality in cancer survivors. Senolytics, drugs that selectively kill senescent cells, have been developed recently and have been proposed as second-line adjuvant tumour therapy. Similarly, by blocking accelerated senescence following therapy, senolytics might prevent and potentially even revert premature frailty in cancer survivors. Adjuvant senostatic interventions, which suppress senescence-associated bystander signalling, might also have therapeutic potential. This becomes pertinent because treatments that are senostatic in vitro (e.g. dietary restriction mimetics) persistently reduce numbers of senescent cells in vivo, i.e. act as net senolytics in immunocompetent hosts.
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Affiliation(s)
- Susan Short
- Leeds Institute of Cancer and Pathology, Wellcome Trust Brenner Building, St James's University Hospital, Beckett St, Leeds LS9 7TF, UK
| | - Edward Fielder
- Newcastle University Institute for Ageing, Institute for Cell and Molecular Biology, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne NE4 5PL, UK
| | - Satomi Miwa
- Newcastle University Institute for Ageing, Institute for Cell and Molecular Biology, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne NE4 5PL, UK
| | - Thomas von Zglinicki
- Newcastle University Institute for Ageing, Institute for Cell and Molecular Biology, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne NE4 5PL, UK.
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