1
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Meyer DH, Schumacher B. Aging clocks based on accumulating stochastic variation. NATURE AGING 2024; 4:871-885. [PMID: 38724736 PMCID: PMC11186771 DOI: 10.1038/s43587-024-00619-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 03/28/2024] [Indexed: 05/15/2024]
Abstract
Aging clocks have provided one of the most important recent breakthroughs in the biology of aging, and may provide indicators for the effectiveness of interventions in the aging process and preventive treatments for age-related diseases. The reproducibility of accurate aging clocks has reinvigorated the debate on whether a programmed process underlies aging. Here we show that accumulating stochastic variation in purely simulated data is sufficient to build aging clocks, and that first-generation and second-generation aging clocks are compatible with the accumulation of stochastic variation in DNA methylation or transcriptomic data. We find that accumulating stochastic variation is sufficient to predict chronological and biological age, indicated by significant prediction differences in smoking, calorie restriction, heterochronic parabiosis and partial reprogramming. Although our simulations may not explicitly rule out a programmed aging process, our results suggest that stochastically accumulating changes in any set of data that have a ground state at age zero are sufficient for generating aging clocks.
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Affiliation(s)
- David H Meyer
- Institute for Genome Stability in Aging and Disease, University Hospital and University of Cologne, Cologne, Germany.
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
| | - Björn Schumacher
- Institute for Genome Stability in Aging and Disease, University Hospital and University of Cologne, Cologne, Germany.
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
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2
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Pio-Lopez L, Levin M. Aging as a loss of morphostatic information: A developmental bioelectricity perspective. Ageing Res Rev 2024; 97:102310. [PMID: 38636560 DOI: 10.1016/j.arr.2024.102310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 02/21/2024] [Accepted: 04/12/2024] [Indexed: 04/20/2024]
Abstract
Maintaining order at the tissue level is crucial throughout the lifespan, as failure can lead to cancer and an accumulation of molecular and cellular disorders. Perhaps, the most consistent and pervasive result of these failures is aging, which is characterized by the progressive loss of function and decline in the ability to maintain anatomical homeostasis and reproduce. This leads to organ malfunction, diseases, and ultimately death. The traditional understanding of aging is that it is caused by the accumulation of molecular and cellular damage. In this article, we propose a complementary view of aging from the perspective of endogenous bioelectricity which has not yet been integrated into aging research. We propose a view of aging as a morphostasis defect, a loss of biophysical prepattern information, encoding anatomical setpoints used for dynamic tissue and organ homeostasis. We hypothesize that this is specifically driven by abrogation of the endogenous bioelectric signaling that normally harnesses individual cell behaviors toward the creation and upkeep of complex multicellular structures in vivo. Herein, we first describe bioelectricity as the physiological software of life, and then identify and discuss the links between bioelectricity and life extension strategies and age-related diseases. We develop a bridge between aging and regeneration via bioelectric signaling that suggests a research program for healthful longevity via morphoceuticals. Finally, we discuss the broader implications of the homologies between development, aging, cancer and regeneration and how morphoceuticals can be developed for aging.
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Affiliation(s)
- Léo Pio-Lopez
- Allen Discovery Center, Tufts University, Medford, MA 02155, USA
| | - Michael Levin
- Allen Discovery Center, Tufts University, Medford, MA 02155, USA; Wyss Institute for Biologically Inspired Engineering, Boston, MA 02115, USA.
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3
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Islam M, Behura SK. Molecular Regulation of Fetal Brain Development in Inbred and Congenic Mouse Strains Differing in Longevity. Genes (Basel) 2024; 15:604. [PMID: 38790233 PMCID: PMC11121069 DOI: 10.3390/genes15050604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 05/04/2024] [Accepted: 05/08/2024] [Indexed: 05/26/2024] Open
Abstract
The objective of this study was to investigate gene regulation of the developing fetal brain from congenic or inbred mice strains that differed in longevity. Gene expression and alternative splice variants were analyzed in a genome-wide manner in the fetal brain of C57BL/6J mice (long-lived) in comparison to B6.Cg-Cav1tm1Mls/J (congenic, short-lived) and AKR/J (inbred, short-lived) mice on day(d) 12, 15, and 17 of gestation. The analysis showed a contrasting gene expression pattern during fetal brain development in these mice. Genes related to brain development, aging, and the regulation of alternative splicing were significantly differentially regulated in the fetal brain of the short-lived compared to long-lived mice during development from d15 and d17. A significantly reduced number of splice variants was observed on d15 compared to d12 or d17 in a strain-dependent manner. An epigenetic clock analysis of d15 fetal brain identified DNA methylations that were significantly associated with single-nucleotide polymorphic sites between AKR/J and C57BL/6J strains. These methylations were associated with genes that show epigenetic changes in an age-correlated manner in mice. Together, the finding of this study suggest that fetal brain development and longevity are epigenetically linked, supporting the emerging concept of the early-life origin of longevity.
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Affiliation(s)
- Maliha Islam
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Susanta K. Behura
- Division of Animal Sciences, University of Missouri, Columbia, MO 65211, USA
- MU Institute for Data Science and Informatics, University of Missouri, Columbia, MO 65211, USA
- Interdisciplinary Reproduction and Health Group, University of Missouri, Columbia, MO 65211, USA
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO 65211, USA
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4
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Bylino OV, Ogienko AA, Batin MA, Georgiev PG, Omelina ES. Genetic, Environmental, and Stochastic Components of Lifespan Variability: The Drosophila Paradigm. Int J Mol Sci 2024; 25:4482. [PMID: 38674068 PMCID: PMC11050664 DOI: 10.3390/ijms25084482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 03/25/2024] [Accepted: 04/05/2024] [Indexed: 04/28/2024] Open
Abstract
Lifespan is a complex quantitative trait involving genetic and non-genetic factors as well as the peculiarities of ontogenesis. As with all quantitative traits, lifespan shows considerable variation within populations and between individuals. Drosophila, a favourite object of geneticists, has greatly advanced our understanding of how different forms of variability affect lifespan. This review considers the role of heritable genetic variability, phenotypic plasticity and stochastic variability in controlling lifespan in Drosophila melanogaster. We discuss the major historical milestones in the development of the genetic approach to study lifespan, the breeding of long-lived lines, advances in lifespan QTL mapping, the environmental factors that have the greatest influence on lifespan in laboratory maintained flies, and the mechanisms, by which individual development affects longevity. The interplay between approaches to study ageing and lifespan limitation will also be discussed. Particular attention will be paid to the interaction of different types of variability in the control of lifespan.
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Affiliation(s)
- Oleg V. Bylino
- Department of Regulation of Genetic Processes, Laboratory of Molecular Organization of the Genome, Institute of Gene Biology RAS, 119334 Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Anna A. Ogienko
- Department of Regulation of Genetic Processes, Institute of Molecular and Cellular Biology SB RAS, 630090 Novosibirsk, Russia
| | - Mikhail A. Batin
- Open Longevity, 15260 Ventura Blvd., Sherman Oaks, Los Angeles, CA 91403, USA
| | - Pavel G. Georgiev
- Department of Regulation of Genetic Processes, Laboratory of Molecular Organization of the Genome, Institute of Gene Biology RAS, 119334 Moscow, Russia
| | - Evgeniya S. Omelina
- Department of Regulation of Genetic Processes, Institute of Molecular and Cellular Biology SB RAS, 630090 Novosibirsk, Russia
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5
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Pandey T, Wang B, Wang C, Zu J, Deng H, Shen K, do Vale GD, McDonald JG, Ma DK. LPD-3 as a megaprotein brake for aging and insulin-mTOR signaling in C. elegans. Cell Rep 2024; 43:113899. [PMID: 38446666 PMCID: PMC11019932 DOI: 10.1016/j.celrep.2024.113899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 01/21/2024] [Accepted: 02/15/2024] [Indexed: 03/08/2024] Open
Abstract
Insulin-mechanistic target of rapamycin (mTOR) signaling drives anabolic growth during organismal development; its late-life dysregulation contributes to aging and limits lifespans. Age-related regulatory mechanisms and functional consequences of insulin-mTOR remain incompletely understood. Here, we identify LPD-3 as a megaprotein that orchestrates the tempo of insulin-mTOR signaling during C. elegans aging. We find that an agonist insulin, INS-7, is drastically overproduced from early life and shortens lifespan in lpd-3 mutants. LPD-3 forms a bridge-like tunnel megaprotein to facilitate non-vesicular cellular lipid trafficking. Lipidomic profiling reveals increased hexaceramide species in lpd-3 mutants, accompanied by up-regulation of hexaceramide biosynthetic enzymes, including HYL-1. Reducing the abundance of HYL-1, insulin receptor/DAF-2 or mTOR/LET-363, normalizes INS-7 levels and rescues the lifespan of lpd-3 mutants. LPD-3 antagonizes SINH-1, a key mTORC2 component, and decreases expression with age. We propose that LPD-3 acts as a megaprotein brake for organismal aging and that its age-dependent decline restricts lifespan through the sphingolipid-hexaceramide and insulin-mTOR pathways.
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Affiliation(s)
- Taruna Pandey
- Cardiovascular Research Institute and Department of Physiology, University of California San Francisco, San Francisco, CA, USA
| | - Bingying Wang
- Cardiovascular Research Institute and Department of Physiology, University of California San Francisco, San Francisco, CA, USA
| | - Changnan Wang
- Cardiovascular Research Institute and Department of Physiology, University of California San Francisco, San Francisco, CA, USA
| | - Jenny Zu
- Cardiovascular Research Institute and Department of Physiology, University of California San Francisco, San Francisco, CA, USA
| | - Huichao Deng
- Department of Biology, Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Kang Shen
- Department of Biology, Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Goncalo Dias do Vale
- Center for Human Nutrition and Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jeffrey G McDonald
- Center for Human Nutrition and Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Dengke K Ma
- Cardiovascular Research Institute and Department of Physiology, University of California San Francisco, San Francisco, CA, USA; Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA, USA.
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6
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Lemaître JF, Moorad J, Gaillard JM, Maklakov AA, Nussey DH. A unified framework for evolutionary genetic and physiological theories of aging. PLoS Biol 2024; 22:e3002513. [PMID: 38412150 PMCID: PMC10898761 DOI: 10.1371/journal.pbio.3002513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024] Open
Abstract
Why and how we age are 2 intertwined questions that have fascinated scientists for many decades. However, attempts to answer these questions remain compartmentalized, preventing a comprehensive understanding of the aging process. We argue that the current lack of knowledge about the evolution of aging mechanisms is due to a lack of clarity regarding evolutionary theories of aging that explicitly involve physiological processes: the disposable soma theory (DST) and the developmental theory of aging (DTA). In this Essay, we propose a new hierarchical model linking genes to vital rates, enabling us to critically reevaluate the DST and DTA in terms of their relationship to evolutionary genetic theories of aging (mutation accumulation (MA) and antagonistic pleiotropy (AP)). We also demonstrate how these 2 theories can be incorporated in a unified hierarchical framework. The new framework will help to generate testable hypotheses of how the hallmarks of aging are shaped by natural selection.
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Affiliation(s)
- Jean-François Lemaître
- Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Évolutive UMR 5558, Villeurbanne, France
| | - Jacob Moorad
- Institute of Ecology & Evolution, School of Biological Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Jean-Michel Gaillard
- Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Évolutive UMR 5558, Villeurbanne, France
| | - Alexei A. Maklakov
- School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
| | - Daniel H. Nussey
- Institute of Ecology & Evolution, School of Biological Science, University of Edinburgh, Edinburgh, United Kingdom
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7
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Mozhui K, Kim H, Villani F, Haghani A, Sen S, Horvath S. Pleiotropic influence of DNA methylation QTLs on physiological and ageing traits. Epigenetics 2023; 18:2252631. [PMID: 37691384 PMCID: PMC10496549 DOI: 10.1080/15592294.2023.2252631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 07/31/2023] [Accepted: 08/16/2023] [Indexed: 09/12/2023] Open
Abstract
DNA methylation is influenced by genetic and non-genetic factors. Here, we chart quantitative trait loci (QTLs) that modulate levels of methylation at highly conserved CpGs using liver methylome data from mouse strains belonging to the BXD family. A regulatory hotspot on chromosome 5 had the highest density of trans-acting methylation QTLs (trans-meQTLs) associated with multiple distant CpGs. We refer to this locus as meQTL.5a. Trans-modulated CpGs showed age-dependent changes and were enriched in developmental genes, including several members of the MODY pathway (maturity onset diabetes of the young). The joint modulation by genotype and ageing resulted in a more 'aged methylome' for BXD strains that inherited the DBA/2J parental allele at meQTL.5a. Further, several gene expression traits, body weight, and lipid levels mapped to meQTL.5a, and there was a modest linkage with lifespan. DNA binding motif and protein-protein interaction enrichment analyses identified the hepatic nuclear factor, Hnf1a (MODY3 gene in humans), as a strong candidate. The pleiotropic effects of meQTL.5a could contribute to variations in body size and metabolic traits, and influence CpG methylation and epigenetic ageing that could have an impact on lifespan.
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Affiliation(s)
- Khyobeni Mozhui
- Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Hyeonju Kim
- Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Flavia Villani
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Amin Haghani
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
- Altos Labs, San Diego, CA, USA
| | - Saunak Sen
- Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Steve Horvath
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
- Altos Labs, San Diego, CA, USA
- Department of Biostatistics, Fielding School of Public Health, University of California Los Angeles, Los Angeles, CA, USA
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8
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Kern CC, Srivastava S, Ezcurra M, Hsiung KC, Hui N, Townsend S, Maczik D, Zhang B, Tse V, Konstantellos V, Bähler J, Gems D. C. elegans ageing is accelerated by a self-destructive reproductive programme. Nat Commun 2023; 14:4381. [PMID: 37474586 PMCID: PMC10359416 DOI: 10.1038/s41467-023-40088-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 07/12/2023] [Indexed: 07/22/2023] Open
Abstract
In post-reproductive C. elegans, destructive somatic biomass repurposing supports production of yolk which, it was recently shown, is vented and can serve as a foodstuff for larval progeny. This is reminiscent of the suicidal reproductive effort (reproductive death) typical of semelparous organisms such as Pacific salmon. To explore the possibility that C. elegans exhibits reproductive death, we have compared sibling species pairs of the genera Caenorhabditis and Pristionchus with hermaphrodites and females. We report that yolk venting and constitutive, early pathology involving major anatomical changes occur only in hermaphrodites, which are also shorter lived. Moreover, only in hermaphrodites does germline removal suppress senescent pathology and markedly increase lifespan. This is consistent with the hypothesis that C. elegans exhibit reproductive death that is suppressed by germline ablation. If correct, this would imply a major difference in the ageing process between C. elegans and most higher organisms, and potentially explain the exceptional plasticity in C. elegans ageing.
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Affiliation(s)
- Carina C Kern
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - Shivangi Srivastava
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - Marina Ezcurra
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
- School of Biosciences, Stacey Building, University of Kent, Canterbury, Kent, CT2 7NJ, UK
| | - Kuei Ching Hsiung
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - Nancy Hui
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - StJohn Townsend
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
- Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, London, NW1 1AT, UK
| | - Dominik Maczik
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - Bruce Zhang
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - Victoria Tse
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - Viktoras Konstantellos
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - Jürg Bähler
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - David Gems
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK.
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9
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Mc Auley MT. An evolutionary perspective of lifespan and epigenetic inheritance. Exp Gerontol 2023; 179:112256. [PMID: 37460026 DOI: 10.1016/j.exger.2023.112256] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 07/04/2023] [Accepted: 07/12/2023] [Indexed: 07/21/2023]
Abstract
In the last decade epigenetics has come to the fore as a discipline which is central to biogerontology. Age associated epigenetic changes are routinely linked with pathologies, including cardiovascular disease, cancer, and Alzheimer's disease; moreover, epigenetic clocks are capable of correlating biological age with chronological age in many species including humans. Recent intriguing empirical observations also suggest that inherited epigenetic effects could influence lifespan/longevity in a variety of organisms. If this is the case, an imperative exists to reconcile lifespan/longevity associated inherited epigenetic processes with the evolution of ageing. This review will critically evaluate inherited epigenetic effects from an evolutionary perspective. The overarching aim is to integrate the evidence which suggests epigenetic inheritance modulates lifespan/longevity with the main evolutionary theories of ageing.
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10
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Pandey T, Wang B, Wang C, Zu J, Deng H, Shen K, do Vale GD, McDonald JG, Ma DK. LPD-3 as a megaprotein brake for aging and insulin-mTOR signaling in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.14.528431. [PMID: 36824874 PMCID: PMC9949100 DOI: 10.1101/2023.02.14.528431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Insulin-mTOR signaling drives anabolic growth during organismal development, while its late-life dysregulation may detrimentally contribute to aging and limit lifespans. Age-related regulatory mechanisms and functional consequences of insulin-mTOR remain incompletely understood. Here we identify LPD-3 as a megaprotein that orchestrates the tempo of insulin-mTOR signaling during C. elegans aging. We find that an agonist insulin INS-7 is drastically over-produced in early life and shortens lifespan in lpd-3 mutants, a C. elegans model of human Alkuraya-Kučinskas syndrome. LPD-3 forms a bridge-like tunnel megaprotein to facilitate phospholipid trafficking to plasma membranes. Lipidomic profiling reveals increased abundance of hexaceramide species in lpd-3 mutants, accompanied by up-regulation of hexaceramide biosynthetic enzymes, including HYL-1 (Homolog of Yeast Longevity). Reducing HYL-1 activity decreases INS-7 levels and rescues the lifespan of lpd-3 mutants through insulin receptor/DAF-2 and mTOR/LET-363. LPD3 antagonizes SINH-1, a key mTORC2 component, and decreases expression with age in wild type animals. We propose that LPD-3 acts as a megaprotein brake for aging and its age-dependent decline restricts lifespan through the sphingolipid-hexaceramide and insulin-mTOR pathways.
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Affiliation(s)
- Taruna Pandey
- Cardiovascular Research Institute and Department of Physiology, University of California San Francisco, San Francisco, USA
| | - Bingying Wang
- Cardiovascular Research Institute and Department of Physiology, University of California San Francisco, San Francisco, USA
| | - Changnan Wang
- Cardiovascular Research Institute and Department of Physiology, University of California San Francisco, San Francisco, USA
| | - Jenny Zu
- Cardiovascular Research Institute and Department of Physiology, University of California San Francisco, San Francisco, USA
| | - Huichao Deng
- Department of Biology, Howard Hughes Medical Institute, Stanford University, Stanford, USA
| | - Kang Shen
- Department of Biology, Howard Hughes Medical Institute, Stanford University, Stanford, USA
| | - Goncalo Dias do Vale
- Center for Human Nutrition and Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, USA
| | - Jeffrey G. McDonald
- Center for Human Nutrition and Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, USA
| | - Dengke K. Ma
- Cardiovascular Research Institute and Department of Physiology, University of California San Francisco, San Francisco, USA
- Innovative Genomics Institute, University of California, Berkeley, USA
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11
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Singh P, Gollapalli K, Mangiola S, Schranner D, Yusuf MA, Chamoli M, Shi SL, Bastos BL, Nair T, Riermeier A, Vayndorf EM, Wu JZ, Nilakhe A, Nguyen CQ, Muir M, Kiflezghi MG, Foulger A, Junker A, Devine J, Sharan K, Chinta SJ, Rajput S, Rane A, Baumert P, Schönfelder M, Iavarone F, Lorenzo GD, Kumari S, Gupta A, Sarkar R, Khyriem C, Chawla AS, Sharma A, Sarper N, Chattopadhyay N, Biswal BK, Settembre C, Nagarajan P, Targoff KL, Picard M, Gupta S, Velagapudi V, Papenfuss AT, Kaya A, Ferreira MG, Kennedy BK, Andersen JK, Lithgow GJ, Ali AM, Mukhopadhyay A, Palotie A, Kastenmüller G, Kaeberlein M, Wackerhage H, Pal B, Yadav VK. Taurine deficiency as a driver of aging. Science 2023; 380:eabn9257. [PMID: 37289866 PMCID: PMC10630957 DOI: 10.1126/science.abn9257] [Citation(s) in RCA: 64] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Accepted: 04/14/2023] [Indexed: 06/10/2023]
Abstract
Aging is associated with changes in circulating levels of various molecules, some of which remain undefined. We find that concentrations of circulating taurine decline with aging in mice, monkeys, and humans. A reversal of this decline through taurine supplementation increased the health span (the period of healthy living) and life span in mice and health span in monkeys. Mechanistically, taurine reduced cellular senescence, protected against telomerase deficiency, suppressed mitochondrial dysfunction, decreased DNA damage, and attenuated inflammaging. In humans, lower taurine concentrations correlated with several age-related diseases and taurine concentrations increased after acute endurance exercise. Thus, taurine deficiency may be a driver of aging because its reversal increases health span in worms, rodents, and primates and life span in worms and rodents. Clinical trials in humans seem warranted to test whether taurine deficiency might drive aging in humans.
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Affiliation(s)
- Parminder Singh
- Metabolic Research Laboratories, National Institute of Immunology; New Delhi, India
| | - Kishore Gollapalli
- Vagelos College of Physicians and Surgeons, Columbia University; New York, USA
| | - Stefano Mangiola
- Department of Medical Biology, University of Melbourne; Melbourne, Australia
- School of Cancer Medicine, La Trobe University; Bundoora, Australia
- Olivia Newton-John Cancer Research Institute; Heidelberg, Australia
| | - Daniela Schranner
- Exercise Biology Group, Technical University of Munich; Munich, Germany
- Institute of Computational Biology, Helmholtz Zentrum München; Neuherberg, Germany
| | - Mohd Aslam Yusuf
- Department of Bioengineering, Integral University; Lucknow, India
| | - Manish Chamoli
- Buck Institute of Age Research, 8001 Redwood Blvd; California, USA
| | - Sting L. Shi
- Vagelos College of Physicians and Surgeons, Columbia University; New York, USA
| | - Bruno Lopes Bastos
- Institute for Research on Cancer and Aging of Nice (IRCAN); Nice, France
| | - Tripti Nair
- Molecular Aging Laboratory, National Institute of Immunology; New Delhi, India
| | - Annett Riermeier
- Exercise Biology Group, Technical University of Munich; Munich, Germany
| | - Elena M. Vayndorf
- Department of Laboratory Medicine and Pathology, University of Washington; WA, USA
| | - Judy Z. Wu
- Department of Laboratory Medicine and Pathology, University of Washington; WA, USA
| | - Aishwarya Nilakhe
- Metabolic Research Laboratories, National Institute of Immunology; New Delhi, India
| | - Christina Q. Nguyen
- Department of Laboratory Medicine and Pathology, University of Washington; WA, USA
| | - Michael Muir
- Department of Laboratory Medicine and Pathology, University of Washington; WA, USA
| | - Michael G. Kiflezghi
- Department of Laboratory Medicine and Pathology, University of Washington; WA, USA
| | - Anna Foulger
- Buck Institute of Age Research, 8001 Redwood Blvd; California, USA
| | - Alex Junker
- Department of Neurology, Columbia University; New York, USA
| | - Jack Devine
- Department of Neurology, Columbia University; New York, USA
| | - Kunal Sharan
- Mouse Genetics Project, Wellcome Sanger Institute; Cambridge, UK
| | | | - Swati Rajput
- Division of Endocrinology, CSIR-Central Drug Research Institute; Lucknow, India
| | - Anand Rane
- Buck Institute of Age Research, 8001 Redwood Blvd; California, USA
| | - Philipp Baumert
- Exercise Biology Group, Technical University of Munich; Munich, Germany
| | | | | | | | - Swati Kumari
- Metabolic Research Laboratories, National Institute of Immunology; New Delhi, India
| | - Alka Gupta
- Metabolic Research Laboratories, National Institute of Immunology; New Delhi, India
| | - Rajesh Sarkar
- Metabolic Research Laboratories, National Institute of Immunology; New Delhi, India
| | - Costerwell Khyriem
- Harry Perkins Institute of Medical Research; Perth, Australia
- Curtin Medical School, Curtin University; Perth, Australia
| | - Amanpreet S. Chawla
- Immunobiology Laboratory, National Institute of Immunology; New Delhi, India
- MRC-Protein Phosphorylation and Ubiquitination Unit, University of Dundee; Dundee, UK
| | - Ankur Sharma
- Harry Perkins Institute of Medical Research; Perth, Australia
- Curtin Medical School, Curtin University; Perth, Australia
| | - Nazan Sarper
- Pediatrics and Pediatric Hematology, Kocaeli University Hospital; Kocaeli, Turkey
| | | | - Bichitra K. Biswal
- Metabolic Research Laboratories, National Institute of Immunology; New Delhi, India
| | - Carmine Settembre
- Telethon Institute of Genetics and Medicine (TIGEM); Pozzuoli, Italy
- Department of Clinical Medicine and Surgery, Federico II University; Naples, Italy
| | - Perumal Nagarajan
- Primate Research Facility, National Institute of Immunology; New Delhi, India
- Small Animal Research Facility, National Institute of Immunology; New Delhi, India
| | - Kimara L. Targoff
- Division of Cardiology, Department of Pediatrics, Columbia University; New York, USA
| | - Martin Picard
- Department of Neurology, Columbia University; New York, USA
| | - Sarika Gupta
- Metabolic Research Laboratories, National Institute of Immunology; New Delhi, India
| | - Vidya Velagapudi
- Institute for Molecular Medicine Finland FIMM, University of Helsinki; Helsinki, Finland
| | | | - Alaattin Kaya
- Department of Biology, Virginia Commonwealth University; Virginia, USA
| | | | - Brian K. Kennedy
- Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore; Singapore, Singapore
- Centre for Healthy Longevity, National University Health System; Singapore, Singapore
- Departments of Biochemistry and Physiology, Yong Loo Lin School of Medicine, National University of Singapore; Singapore, Singapore
| | | | | | - Abdullah Mahmood Ali
- Department of Medicine, Columbia University Irving Medical Center; New York, USA
| | - Arnab Mukhopadhyay
- Molecular Aging Laboratory, National Institute of Immunology; New Delhi, India
| | - Aarno Palotie
- Institute for Molecular Medicine Finland FIMM, University of Helsinki; Helsinki, Finland
- Broad Institute of Harvard and MIT; Cambridge, USA
- Analytic and Translational Genetics Unit, Massachusetts General Hospital; Boston, USA
| | - Gabi Kastenmüller
- Institute of Computational Biology, Helmholtz Zentrum München; Neuherberg, Germany
| | - Matt Kaeberlein
- Department of Laboratory Medicine and Pathology, University of Washington; WA, USA
| | | | - Bhupinder Pal
- Department of Medical Biology, University of Melbourne; Melbourne, Australia
- School of Cancer Medicine, La Trobe University; Bundoora, Australia
| | - Vijay K. Yadav
- Metabolic Research Laboratories, National Institute of Immunology; New Delhi, India
- Vagelos College of Physicians and Surgeons, Columbia University; New York, USA
- Mouse Genetics Project, Wellcome Sanger Institute; Cambridge, UK
- Department of Genetics and Development, Columbia University; New York, USA
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12
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Richard D, Capellini TD, Diekman BO. Epigenetics as a mediator of genetic risk in osteoarthritis: role during development, homeostasis, aging, and disease progression. Am J Physiol Cell Physiol 2023; 324:C1078-C1088. [PMID: 36971423 PMCID: PMC10191130 DOI: 10.1152/ajpcell.00574.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/16/2023] [Accepted: 03/16/2023] [Indexed: 03/29/2023]
Abstract
The identification of genomic loci that are associated with osteoarthritis (OA) has provided a starting point for understanding how genetic variation activates catabolic processes in the joint. However, genetic variants can only alter gene expression and cellular function when the epigenetic environment is permissive to these effects. In this review, we provide examples of how epigenetic shifts at distinct life stages can alter the risk for OA, which we posit is critical for the proper interpretation of genome-wide association studies (GWAS). During development, intensive work on the growth and differentiation factor 5 (GDF5) locus has revealed the importance of tissue-specific enhancer activity in controlling both joint development and the subsequent risk for OA. During homeostasis in adults, underlying genetic risk factors may help establish beneficial or catabolic "set points" that dictate tissue function, with a strong cumulative effect on OA risk. During aging, methylation changes and the reorganization of chromatin can "unmask" the effects of genetic variants. The destructive function of variants that alter aging would only mediate effects after reproductive competence and thus avoid any evolutionary selection pressure, as consistent with larger frameworks of biological aging and its relationship to disease. A similar "unmasking" may occur during OA progression, which is supported by the finding of distinct expression quantitative trait loci (eQTLs) in chondrocytes depending on the degree of tissue degradation. Finally, we propose that massively parallel reporter assays (MPRAs) will be a valuable tool to test the function of putative OA GWAS variants in chondrocytes from different life stages.
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Affiliation(s)
- Daniel Richard
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, United States
| | - Terence D Capellini
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, United States
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States
| | - Brian O Diekman
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, and North Carolina State University, Raleigh, North Carolina, United States
- Thurston Arthritis Research Center, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States
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13
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Abstract
Ageing is inherent to all human beings, yet why we age remains a hotly contested topic. Most mechanistic explanations of ageing posit that ageing is caused by the accumulation of one or more forms of molecular damage. Here, I propose that we age not because of inevitable damage to the hardware but rather because of intrinsic design flaws in the software, defined as the DNA code that orchestrates how a single cell develops into an adult organism. As the developmental software runs, its sequence of events is reflected in shifting cellular epigenetic states. Overall, I suggest that to understand ageing we need to decode our software and the flow of epigenetic information throughout the life course.
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Affiliation(s)
- João Pedro de Magalhães
- Genomics of Ageing and Rejuvenation Lab, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, B15 2WB, UK.
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14
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Salnikov L, Goldberg S, Rijhwani H, Shi Y, Pinsky E. The RNA-Seq data analysis shows how the ontogenesis defines aging. FRONTIERS IN AGING 2023; 4:1143334. [PMID: 36999000 PMCID: PMC10046809 DOI: 10.3389/fragi.2023.1143334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 03/03/2023] [Indexed: 03/15/2023]
Abstract
This paper presents a global statistical analysis of the RNA-Seq results of the entire Mus musculus genome. We explain aging by a gradual redistribution of limited resources between two major tasks of the organism: its self-sustenance based on the function of the housekeeping gene group (HG) and functional differentiation provided by the integrative gene group (IntG). All known disorders associated with aging are the result of a deficiency in the repair processes provided by the cellular infrastructure. Understanding exactly how this deficiency arises is our primary goal. Analysis of RNA production data of 35,630 genes, from which 5,101 were identified as HG genes, showed that RNA production levels in the HG and IntG genes had statistically significant differences (p-value <0.0001) throughout the entire observation period. In the reproductive period of life, which has the lowest actual mortality risk for Mus musculus, changes in the age dynamics of RNA production occur. The statistically significant dynamics of the decrease of RNA production in the HG group in contrast to the IntG group was determined (p-value = 0.0045). The trend toward significant shift in the HG/IntG ratio occurs after the end of the reproductive period, coinciding with the beginning of the mortality rate increase in Mus musculus indirectly supports our hypothesis. The results demonstrate a different orientation of the impact of ontogenesis regulatory mechanisms on the groups of genes representing cell infrastructures and their organismal functions, making the chosen direction promising for further research and understanding the mechanisms of aging.
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Affiliation(s)
- Lev Salnikov
- AntiCA Biomed, San Diego, CA, United States
- *Correspondence: Lev Salnikov,
| | - Saveli Goldberg
- Department of Radiation Oncology, Mass General Hospital, Boston, MA, United Kingdom
| | - Heena Rijhwani
- Department of Computer Science, Met College, Boston University, Boston, MA, United Kingdom
| | - Yuran Shi
- Department of Computer Science, Brandeis University, Waltham, MA, United Kingdom
| | - Eugene Pinsky
- Department of Computer Science, Met College, Boston University, Boston, MA, United Kingdom
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15
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Ayala-Guerrero L, Claudio-Galeana S, Furlan-Magaril M, Castro-Obregón S. Chromatin Structure from Development to Ageing. Subcell Biochem 2023; 102:7-51. [PMID: 36600128 DOI: 10.1007/978-3-031-21410-3_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Nuclear structure influences genome architecture, which contributes to determine patterns of gene expression. Global changes in chromatin dynamics are essential during development and differentiation, and are one of the hallmarks of ageing. This chapter describes the molecular dynamics of chromatin structure that occur during development and ageing. In the first part, we introduce general information about the nuclear lamina, the chromatin structure, and the 3D organization of the genome. Next, we detail the molecular hallmarks found during development and ageing, including the role of DNA and histone modifications, 3D genome dynamics, and changes in the nuclear lamina. Within the chapter we discuss the implications that genome structure has on the mechanisms that drive development and ageing, and the physiological consequences when these mechanisms fail.
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Affiliation(s)
- Lorelei Ayala-Guerrero
- Departamento de Neurodesarrollo y Fisiología, Instituto de Fisiología Celular, UNAM, Mexico City, Mexico
| | - Sherlyn Claudio-Galeana
- Departamento de Genética Molecular, Instituto de Fisiología Celular, UNAM, Mexico City, Mexico
| | - Mayra Furlan-Magaril
- Departamento de Genética Molecular, Instituto de Fisiología Celular, UNAM, Mexico City, Mexico.
| | - Susana Castro-Obregón
- Departamento de Neurodesarrollo y Fisiología, Instituto de Fisiología Celular, UNAM, Mexico City, Mexico.
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16
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Salnikov L. Aging is a Side Effect of the Ontogenesis Program of Multicellular Organisms. BIOCHEMISTRY. BIOKHIMIIA 2022; 87:1498-1503. [PMID: 36717443 DOI: 10.1134/s0006297922120070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The review presents a brief outline of the current state of the main theoretical approaches to the aging problem. The works of authors, supporting the theory of "accumulation of errors" and theories stating the presence of a hypothetical "aging program" in all multicellular organisms are reviewed. The role of apoptosis and its connection with phenoptosis, as well as the theory of "hyperfunction" are analyzed. Our own approach to this problem is presented, in which aging is explained by the redistribution of limited resources between the two main aims of the organism: its self-sufficiency, based on the function of the housekeeping genes (HG) group, and functional specialization, provided by the integrative genes (IntG) group. Agreeing with the inseparable connection between aging and the ontogenesis program, the main role in the aging mechanisms is assigned to the redistribution of resources from the HG self-sufficiency genes to the IntGs necessary for the operation of all specialized functions of the organism as a whole. The growing imbalance between HGs and IntGs with age, suggests that switching of cellular resources in favor of IntGs is a side effect of ontogenesis program implementation and the main reason for aging, inherent in the nature of genome functioning under conditions of highly integrated multicellularity. The hypothesis of functional subdivision of the genome also points to the leading role of slow-dividing and postmitotic cells, as the most sensitive to reduction of repair levels, for triggering and realization of the aging process.
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17
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Olovnikov AM. Planetary Metronome as a Regulator of Lifespan and Aging Rate: The Metronomic Hypothesis. BIOCHEMISTRY. BIOKHIMIIA 2022; 87:1640-1650. [PMID: 36717453 DOI: 10.1134/s0006297922120197] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
A metronomic mechanism for the duration control of ontogenetic cycle periods of an animal is proposed. The components of the proposed metronomic system include the ventricular system of the brain, planet Earth as a generator of metronomic signals, and temporal DNA (tDNA) as a substrate that is epigenetically marked to measure elapsed time of ontogenesis. The metronomic system generates repetitive signals in the form of hydrodynamic disturbances in the cerebrospinal fluid (CSF). The metronomic effect arises due to the superposition of two processes - the near-wall unidirectional flow of CSF and oscillations in the movement of the planet. Hydrodynamic impacts of the metronome are transformed into nerve impulses that initiate epigenetic modification of tDNA in neurons, changing the content of factors expressed by this DNA for innervated targets of the body. The duration of ontogenetic cycle periods, including duration of the adult life, depends on the rate of addition of epigenetic marks to tDNA. This rate depends mainly on the frequency of the metronomic signals used by each particular species. But epigenetic modifications can also be influenced by factors that modulate metabolism and the rate of chromatin modifications, such as a calorie-restricted diet.
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Affiliation(s)
- Alexey M Olovnikov
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, 119334, Russia.
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18
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Duxbury EML, Carlsson H, Sales K, Sultanova Z, Immler S, Chapman T, Maklakov AA. Multigenerational downregulation of insulin/IGF-1 signaling in adulthood improves lineage survival, reproduction, and fitness in Caenorhabditis elegans supporting the developmental theory of ageing. Evolution 2022; 76:2829-2845. [PMID: 36199198 PMCID: PMC10092551 DOI: 10.1111/evo.14640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 07/18/2022] [Accepted: 09/08/2022] [Indexed: 01/22/2023]
Abstract
Adulthood-only downregulation of insulin/IGF-1 signaling (IIS), an evolutionarily conserved pathway regulating resource allocation between somatic maintenance and reproduction, increases life span without fecundity cost in the nematode, Caenorhabditis elegans. However, long-term multigenerational effects of reduced IIS remain unexplored and are proposed to carry costs for offspring quality. To test this hypothesis, we ran a mutation accumulation (MA) experiment and downregulated IIS in half of the 400 MA lines by silencing daf-2 gene expression using RNA interference (RNAi) across 40 generations. Contrary to the prediction, adulthood-only daf-2 RNAi reduced extinction of MA lines both under UV-induced and spontaneous MA. Fitness of the surviving UV-induced MA lines was higher under daf-2 RNAi. Reduced IIS increased intergenerational F1 offspring fitness under UV stress but had no quantifiable transgenerational effects. Functional hrde-1 was required for the benefits of multigenerational daf-2 RNAi. Overall, we found net benefit to fitness from multigenerational reduction of IIS and the benefits became more apparent under stress. Because reduced daf-2 expression during development carries fitness costs, we suggest that our findings are best explained by the developmental theory of ageing, which maintains that the decline in the force of selection with age results in poorly regulated gene expression in adulthood.
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Affiliation(s)
- Elizabeth M L Duxbury
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Hanne Carlsson
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Kris Sales
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Zahida Sultanova
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Simone Immler
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Tracey Chapman
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Alexei A Maklakov
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
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19
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Gems D, Kern CC. Is "cellular senescence" a misnomer? GeroScience 2022; 44:2461-2469. [PMID: 36068483 PMCID: PMC9768054 DOI: 10.1007/s11357-022-00652-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 08/25/2022] [Indexed: 01/06/2023] Open
Abstract
One of the most striking findings in biogerontology in the 2010s was the demonstration that elimination of senescent cells delays many late-life diseases and extends lifespan in mice. This implied that accumulation of senescent cells promotes late-life diseases, particularly through action of senescent cell secretions (the senescence-associated secretory phenotype, or SASP). But what exactly is a senescent cell? Subsequent to the initial characterization of cellular senescence, it became clear that, prior to aging, this phenomenon is in fact adaptive. It supports tissue remodeling functions in a variety of contexts, including embryogenesis, parturition, and acute inflammatory processes that restore normal tissue architecture and function, such as wound healing, tissue repair after infection, and amphibian limb regeneration. In these contexts, such cells are normal and healthy and not in any way senescent in the true sense of the word, as originally meant by Hayflick. Thus, it is misleading to refer to them as "senescent." Similarly, the common assertion that senescent cells accumulate with age due to stress and DNA damage is no longer safe, particularly given their role in inflammation-a process that becomes persistent in later life. We therefore suggest that it would be useful to update some terminology, to bring it into line with contemporary understanding, and to avoid future confusion. To open a discussion of this issue, we propose replacing the term cellular senescence with remodeling activation, and SASP with RASP (remodeling-associated secretory phenotype).
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Affiliation(s)
- David Gems
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT UK
| | - Carina C. Kern
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT UK
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20
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Islam M, Strawn M, Behura SK. Fetal origin of sex‐bias brain aging. FASEB J 2022; 36:e22463. [DOI: 10.1096/fj.202200255rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 06/30/2022] [Accepted: 07/11/2022] [Indexed: 02/01/2023]
Affiliation(s)
- Maliha Islam
- Division of Animal Sciences University of Missouri Columbia Missouri USA
| | - Monica Strawn
- Division of Animal Sciences University of Missouri Columbia Missouri USA
| | - Susanta K. Behura
- Division of Animal Sciences University of Missouri Columbia Missouri USA
- MU Institute for Data Science and Informatics University of Missouri Columbia Missouri USA
- Interdisciplinary Neuroscience Program University of Missouri Columbia Missouri USA
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21
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Gems D. The hyperfunction theory: An emerging paradigm for the biology of aging. Ageing Res Rev 2022; 74:101557. [PMID: 34990845 PMCID: PMC7612201 DOI: 10.1016/j.arr.2021.101557] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 12/24/2021] [Accepted: 12/30/2021] [Indexed: 12/13/2022]
Abstract
The process of senescence (aging) is predominantly determined by the action of wild-type genes. For most organisms, this does not reflect any adaptive function that senescence serves, but rather evolutionary effects of declining selection against genes with deleterious effects later in life. To understand aging requires an account of how evolutionary mechanisms give rise to pathogenic gene action and late-life disease, that integrates evolutionary (ultimate) and mechanistic (proximate) causes into a single explanation. A well-supported evolutionary explanation by G.C. Williams argues that senescence can evolve due to pleiotropic effects of alleles with antagonistic effects on fitness and late-life health (antagonistic pleiotropy, AP). What has remained unclear is how gene action gives rise to late-life disease pathophysiology. One ultimate-proximate account is T.B.L. Kirkwood's disposable soma theory. Based on the hypothesis that stochastic molecular damage causes senescence, this reasons that aging is coupled to reproductive fitness due to preferential investment of resources into reproduction, rather than somatic maintenance. An alternative and more recent ultimate-proximate theory argues that aging is largely caused by programmatic, developmental-type mechanisms. Here ideas about AP and programmatic aging are reviewed, particularly those of M.V. Blagosklonny (the hyperfunction theory) and J.P. de Magalhães (the developmental theory), and their capacity to make sense of diverse experimental findings is assessed.
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Affiliation(s)
- David Gems
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK.
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22
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Izgi H, Han D, Isildak U, Huang S, Kocabiyik E, Khaitovich P, Somel M, Dönertaş HM. Inter-tissue convergence of gene expression during ageing suggests age-related loss of tissue and cellular identity. eLife 2022; 11:68048. [PMID: 35098922 PMCID: PMC8880995 DOI: 10.7554/elife.68048] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 01/28/2022] [Indexed: 11/13/2022] Open
Abstract
Developmental trajectories of gene expression may reverse in their direction during ageing, a phenomenon previously linked to cellular identity loss. Our analysis of cerebral cortex, lung, liver and muscle transcriptomes of 16 mice, covering development and ageing intervals, revealed widespread but tissue-specific ageing-associated expression reversals. Cumulatively, these reversals create a unique phenomenon: mammalian tissue transcriptomes diverge from each other during postnatal development, but during ageing, they tend to converge towards similar expression levels, a process we term Divergence followed by Convergence, or DiCo. We found that DiCo was most prevalent among tissue-specific genes and associated with loss of tissue identity, which is confirmed using data from independent mouse and human datasets. Further, using publicly available single-cell transcriptome data, we showed that DiCo could be driven both by alterations in tissue cell type composition and also by cell-autonomous expression changes within particular cell types.
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Affiliation(s)
- Hamit Izgi
- Department of Biological Sciences, Middle East Technical University, Ankara, Turkey
| | - DingDing Han
- CAS Key Laboratory of Computational Biology, Shanghai Institutes for Biological Sciences, Shanghai, China
| | - Ulas Isildak
- Department of Biological Sciences, Middle East Technical University, Ankara, Turkey
| | - Shuyun Huang
- CAS Key Laboratory of Computational Biology, Shanghai Institutes for Biological Sciences, Shanghai, China
| | - Ece Kocabiyik
- Department of Biological Sciences, Middle East Technical University, Ankara, Turkey
| | - Philipp Khaitovich
- Center for Neurobiology and Brain Restoration, Skolkovo Institute of Science and Technology, Moscow, Russian Federation
| | - Mehmet Somel
- Department of Biological Sciences, Middle East Technical University, Ankara, Turkey
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23
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Effects of prenatal testosterone on cumulative markers of oxidative damage to organs of young adult zebra finches (Taeniopygia guttata). J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2022; 208:303-312. [PMID: 35048181 DOI: 10.1007/s00359-021-01525-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 11/16/2021] [Accepted: 11/19/2021] [Indexed: 10/19/2022]
Abstract
We tested the hypothesis that exposure of avian embryos to androgens in ovo entails long-term costs in the form of oxidative damage to vital cells and organs in adulthood. We injected zebra finch eggs with testosterone (T), monitored postnatal growth, and analyzed markers of oxidative damage in heart and liver in mature birds. We measured 8-oxo-2'-deoxyguanosine and isoprostanes, markers of oxidative damage to DNA and membrane lipids, respectively. T treatment (1) reduced growth rates of female but not male nestlings vs. controls; (2) resulted in less accumulation of 8-oxo-dG, but not IsoPs, in liver tissue of 60-day-old females, but not males; and (3) a trend toward elevated 8-oxo-dG levels in heart tissue of males and females at 60 and 180 days old combined. These results generally support the testosterone oxidative damage hypothesis, in that embryonic exposure to higher T resulted in damage to DNA of heart tissue in both sexes. They also suggest that sex-specific effects of androgens on early growth rates may carry over as differences in some forms of oxidative damage in adults. This supports a basic tenet of evolutionary aging theory that developmental influences early in life can be linked to costs later on.
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24
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Mc Auley MT. DNA methylation in genes associated with the evolution of ageing and disease: A critical review. Ageing Res Rev 2021; 72:101488. [PMID: 34662746 DOI: 10.1016/j.arr.2021.101488] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/30/2021] [Accepted: 10/12/2021] [Indexed: 12/28/2022]
Abstract
Ageing is characterised by a physical decline in biological functioning which results in a progressive risk of mortality with time. As a biological phenomenon, it is underpinned by the dysregulation of a myriad of complex processes. Recently, however, ever-increasing evidence has associated epigenetic mechanisms, such as DNA methylation (DNAm) with age-onset pathologies, including cancer, cardiovascular disease, and Alzheimer's disease. These diseases compromise healthspan. Consequently, there is a medical imperative to understand the link between epigenetic ageing, and healthspan. Evolutionary theory provides a unique way to gain new insights into epigenetic ageing and health. This review will: (1) provide a brief overview of the main evolutionary theories of ageing; (2) discuss recent genetic evidence which has revealed alleles that have pleiotropic effects on fitness at different ages in humans; (3) consider the effects of DNAm on pleiotropic alleles, which are associated with age related disease; (4) discuss how age related DNAm changes resonate with the mutation accumulation, disposable soma and programmed theories of ageing; (5) discuss how DNAm changes associated with caloric restriction intersect with the evolution of ageing; and (6) conclude by discussing how evolutionary theory can be used to inform investigations which quantify age-related DNAm changes which are linked to age onset pathology.
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Affiliation(s)
- Mark Tomás Mc Auley
- Faculty of Science and Engineering, University of Chester, Exton Park, Chester CH1 4BJ, UK.
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25
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Carlsson H, Ivimey-Cook E, Duxbury EML, Edden N, Sales K, Maklakov AA. Ageing as "early-life inertia": Disentangling life-history trade-offs along a lifetime of an individual. Evol Lett 2021; 5:551-564. [PMID: 34621540 PMCID: PMC8484722 DOI: 10.1002/evl3.254] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 07/19/2021] [Accepted: 08/13/2021] [Indexed: 11/10/2022] Open
Abstract
The theory that ageing evolves because of competitive resource allocation between the soma and the germline has been challenged by studies showing that somatic maintenance can be improved without impairing reproduction. However, it has been suggested that cost‐free improvement in somatic maintenance is possible only under a narrow range of benign conditions. Here, we show that experimental downregulation of insulin/IGF‐1 signaling (IIS) in C. elegans nematodes, a robustly reproducible life span‐ and health span‐extending treatment, reduces fitness in a complex variable environment when initiated during development but does not reduce fitness when initiated in adulthood. Thus, our results show that the costs and benefits of reduced IIS can be uncoupled when organisms inhabit variable environments, and, therefore, do not provide support for the resource allocation theory. Our findings support the theory that the force of natural selection on gene expression in evolutionarily conserved signaling pathways that shape life‐history traits declines after the onset of reproduction resulting in organismal senescence.
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Affiliation(s)
- Hanne Carlsson
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | - Edward Ivimey-Cook
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | - Elizabeth M L Duxbury
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | - Nathan Edden
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | - Kris Sales
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | - Alexei A Maklakov
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
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Kern CC, Townsend S, Salzmann A, Rendell NB, Taylor GW, Comisel RM, Foukas LC, Bähler J, Gems D. C. elegans feed yolk to their young in a form of primitive lactation. Nat Commun 2021; 12:5801. [PMID: 34611154 PMCID: PMC8492707 DOI: 10.1038/s41467-021-25821-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 08/27/2021] [Indexed: 11/29/2022] Open
Abstract
The nematode Caenorhabditis elegans exhibits rapid senescence that is promoted by the insulin/IGF-1 signalling (IIS) pathway via regulated processes that are poorly understood. IIS also promotes production of yolk for egg provisioning, which in post-reproductive animals continues in an apparently futile fashion, supported by destructive repurposing of intestinal biomass that contributes to senescence. Here we show that post-reproductive mothers vent yolk which can be consumed by larvae and promotes their growth. This implies that later yolk production is not futile; instead vented yolk functions similarly to milk. Moreover, yolk venting is promoted by IIS. These findings suggest that a self-destructive, lactation-like process effects resource transfer from postreproductive C. elegans mothers to offspring, in a fashion reminiscent of semelparous organisms that reproduce in a single, suicidal burst. That this process is promoted by IIS provides insights into how and why IIS shortens lifespan in C. elegans.
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Affiliation(s)
- Carina C Kern
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - StJohn Townsend
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
- Molecular Biology of Metabolism Laboratory, The Francis Crick Institute, London, NW1 1AT, UK
| | - Antoine Salzmann
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - Nigel B Rendell
- Wolfson Drug Discovery Unit, Centre for Amyloidosis and Acute Phase Proteins, Division of Medicine, University College London, London, NW3 2PF, UK
| | - Graham W Taylor
- Wolfson Drug Discovery Unit, Centre for Amyloidosis and Acute Phase Proteins, Division of Medicine, University College London, London, NW3 2PF, UK
| | - Ruxandra M Comisel
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - Lazaros C Foukas
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - Jürg Bähler
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK
| | - David Gems
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, London, WC1E 6BT, UK.
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Gems D, de Magalhães JP. The hoverfly and the wasp: A critique of the hallmarks of aging as a paradigm. Ageing Res Rev 2021; 70:101407. [PMID: 34271186 PMCID: PMC7611451 DOI: 10.1016/j.arr.2021.101407] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 07/05/2021] [Accepted: 07/11/2021] [Indexed: 01/10/2023]
Abstract
With the goal of representing common denominators of aging in different organisms López-Otín et al. in 2013 described nine hallmarks of aging. Since then, this representation has become a major reference point for the biogerontology field. The template for the hallmarks of aging account originated from landmark papers by Hanahan and Weinberg (2000, 2011) defining first six and later ten hallmarks of cancer. Here we assess the strengths and weaknesses of the hallmarks of aging account. As a checklist of diverse major foci of current aging research, it has provided a useful shared overview for biogerontology during a time of transition in the field. It also seems useful in applied biogerontology, to identify interventions (e.g. drugs) that impact multiple symptomatic features of aging. However, while the hallmarks of cancer provide a paradigmatic account of the causes of cancer with profound explanatory power, the hallmarks of aging do not. A worry is that as a non-paradigm the hallmarks of aging have obscured the urgent need to define a genuine paradigm, one that can provide a useful basis for understanding the mechanistic causes of the diverse aging pathologies. We argue that biogerontology must look and move beyond the hallmarks to understand the process of aging.
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Affiliation(s)
- David Gems
- Institute of Healthy Ageing, and Research Department of Genetics, Evolution and Environment, University College London, Gower Street, London WC1E 6BT, United Kingdom.
| | - João Pedro de Magalhães
- Integrative Genomics of Ageing Group, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool L7 8TX, United Kingdom
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Gems D, Kern CC, Nour J, Ezcurra M. Reproductive Suicide: Similar Mechanisms of Aging in C. elegans and Pacific Salmon. Front Cell Dev Biol 2021; 9:688788. [PMID: 34513830 PMCID: PMC8430333 DOI: 10.3389/fcell.2021.688788] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 07/21/2021] [Indexed: 12/17/2022] Open
Abstract
In some species of salmon, reproductive maturity triggers the development of massive pathology resulting from reproductive effort, leading to rapid post-reproductive death. Such reproductive death, which occurs in many semelparous organisms (with a single bout of reproduction), can be prevented by blocking reproductive maturation, and this can increase lifespan dramatically. Reproductive death is often viewed as distinct from senescence in iteroparous organisms (with multiple bouts of reproduction) such as humans. Here we review the evidence that reproductive death occurs in C. elegans and discuss what this means for its use as a model organism to study aging. Inhibiting insulin/IGF-1 signaling and germline removal suppresses reproductive death and greatly extends lifespan in C. elegans, but can also extend lifespan to a small extent in iteroparous organisms. We argue that mechanisms of senescence operative in reproductive death exist in a less catastrophic form in iteroparous organisms, particularly those that involve costly resource reallocation, and exhibit endocrine-regulated plasticity. Thus, mechanisms of senescence in semelparous organisms (including plants) and iteroparous ones form an etiological continuum. Therefore understanding mechanisms of reproductive death in C. elegans can teach us about some mechanisms of senescence that are operative in iteroparous organisms.
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Affiliation(s)
- David Gems
- Institute of Healthy Ageing, Research Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
| | - Carina C. Kern
- Institute of Healthy Ageing, Research Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
| | - Joseph Nour
- Institute of Healthy Ageing, Research Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
| | - Marina Ezcurra
- School of Biosciences, University of Kent, Canterbury, United Kingdom
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Larocca D, Lee J, West MD, Labat I, Sternberg H. No Time to Age: Uncoupling Aging from Chronological Time. Genes (Basel) 2021; 12:611. [PMID: 33919082 PMCID: PMC8143125 DOI: 10.3390/genes12050611] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 04/13/2021] [Accepted: 04/16/2021] [Indexed: 12/20/2022] Open
Abstract
Multicellular life evolved from simple unicellular organisms that could replicate indefinitely, being essentially ageless. At this point, life split into two fundamentally different cell types: the immortal germline representing an unbroken lineage of cell division with no intrinsic endpoint and the mortal soma, which ages and dies. In this review, we describe the germline as clock-free and the soma as clock-bound and discuss aging with respect to three DNA-based cellular clocks (telomeric, DNA methylation, and transposable element). The ticking of these clocks corresponds to the stepwise progressive limitation of growth and regeneration of somatic cells that we term somatic restriction. Somatic restriction acts in opposition to strategies that ensure continued germline replication and regeneration. We thus consider the plasticity of aging as a process not fixed to the pace of chronological time but one that can speed up or slow down depending on the rate of intrinsic cellular clocks. We further describe how germline factor reprogramming might be used to slow the rate of aging and potentially reverse it by causing the clocks to tick backward. Therefore, reprogramming may eventually lead to therapeutic strategies to treat degenerative diseases by altering aging itself, the one condition common to us all.
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Affiliation(s)
| | - Jieun Lee
- AgeX Therapeutics Inc., Alameda, CA 94501, USA; (J.L.); (M.D.W.); (I.L.); (H.S.)
| | - Michael D. West
- AgeX Therapeutics Inc., Alameda, CA 94501, USA; (J.L.); (M.D.W.); (I.L.); (H.S.)
| | - Ivan Labat
- AgeX Therapeutics Inc., Alameda, CA 94501, USA; (J.L.); (M.D.W.); (I.L.); (H.S.)
| | - Hal Sternberg
- AgeX Therapeutics Inc., Alameda, CA 94501, USA; (J.L.); (M.D.W.); (I.L.); (H.S.)
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Lind MI, Carlsson H, Duxbury EML, Ivimey-Cook E, Maklakov AA. Cost-free lifespan extension via optimization of gene expression in adulthood aligns with the developmental theory of ageing. Proc Biol Sci 2021; 288:20201728. [PMID: 33529563 PMCID: PMC7893226 DOI: 10.1098/rspb.2020.1728] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 01/11/2021] [Indexed: 01/11/2023] Open
Abstract
Ageing evolves because the force of selection on traits declines with age but the proximate causes of ageing are incompletely understood. The 'disposable soma' theory of ageing (DST) upholds that competitive resource allocation between reproduction and somatic maintenance underpins the evolution of ageing and lifespan. In contrast, the developmental theory of ageing (DTA) suggests that organismal senescence is caused by suboptimal gene expression in adulthood. While the DST predicts the trade-off between reproduction and lifespan, the DTA predicts that age-specific optimization of gene expression can increase lifespan without reproduction costs. Here we investigated the consequences for lifespan, reproduction, egg size and individual fitness of early-life, adulthood and post-reproductive onset of RNAi knockdown of five 'longevity' genes involved in key biological processes in Caenorhabditis elegans. Downregulation of these genes in adulthood and/or during post-reproductive period increases lifespan, while we found limited evidence for a link between impaired reproduction and extended lifespan. Our findings demonstrate that suboptimal gene expression in adulthood often contributes to reduced lifespan directly rather than through competitive resource allocation between reproduction and somatic maintenance. Therefore, age-specific optimization of gene expression in evolutionarily conserved signalling pathways that regulate organismal life histories can increase lifespan without fitness costs.
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Affiliation(s)
- Martin I. Lind
- Animal Ecology, Department of Ecology and Genetics, Uppsala University, Uppsala, SE-75236, Sweden
| | - Hanne Carlsson
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| | | | - Edward Ivimey-Cook
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| | - Alexei A. Maklakov
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
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Systems biology reveals reprogramming of the S-nitroso-proteome in the cortical and striatal regions of mice during aging process. Sci Rep 2020; 10:13913. [PMID: 32807865 PMCID: PMC7431412 DOI: 10.1038/s41598-020-70383-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Accepted: 07/28/2020] [Indexed: 12/26/2022] Open
Abstract
Cell aging depends on the rate of cumulative oxidative and nitrosative damage to DNA and proteins. Accumulated data indicate the involvement of protein S-nitrosylation (SNO), the nitric oxide (NO)-mediated posttranslational modification (PTM) of cysteine thiols, in different brain disorders. However, the changes and involvement of SNO in aging including the development of the organism from juvenile to adult state is still unknown. In this study, using the state-of-the-art mass spectrometry technology to identify S-nitrosylated proteins combined with large-scale computational biology, we tested the S-nitroso-proteome in juvenile and adult mice in both cortical and striatal regions. We found reprogramming of the S-nitroso-proteome in adult mice of both cortex and striatum regions. Significant biological processes and protein–protein clusters associated with synaptic and neuronal terms were enriched in adult mice. Extensive quantitative analysis revealed a large set of potentially pathological proteins that were significantly upregulated in adult mice. Our approach, combined with large scale computational biology allowed us to perform a system-level characterization and identification of the key proteins and biological processes that can serve as drug targets for aging and brain disorders in future studies.
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32
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Proikas-Cezanne T, Ktistakis NT. Editorial: Autophagy and Ageing: Ideas, Methods, Molecules. Front Cell Dev Biol 2020; 8:141. [PMID: 32185175 PMCID: PMC7058589 DOI: 10.3389/fcell.2020.00141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 02/20/2020] [Indexed: 01/22/2023] Open
Affiliation(s)
- Tassula Proikas-Cezanne
- Interfaculty Institute of Cell Biology (IFIZ), Eberhard Karls University Tübingen, Tübingen, Germany
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Abstract
Despite tremendous progress in recent years, our understanding of the evolution of ageing is still incomplete. A dominant paradigm maintains that ageing evolves due to the competing energy demands of reproduction and somatic maintenance leading to slow accumulation of unrepaired cellular damage with age. However, the centrality of energy trade-offs in ageing has been increasingly challenged as studies in different organisms have uncoupled the trade-off between reproduction and longevity. An emerging theory is that ageing instead is caused by biological processes that are optimized for early-life function but become harmful when they continue to run-on unabated in late life. This idea builds on the realization that early-life regulation of gene expression can break down in late life because natural selection is too weak to optimize it. Empirical evidence increasingly supports the hypothesis that suboptimal gene expression in adulthood can result in physiological malfunction leading to organismal senescence. We argue that the current state of the art in the study of ageing contradicts the widely held view that energy trade-offs between growth, reproduction, and longevity are the universal underpinning of senescence. Future research should focus on understanding the relative contribution of energy and function trade-offs to the evolution and expression of ageing.
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Affiliation(s)
- Alexei A Maklakov
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Tracey Chapman
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
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34
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MARVELD1 depletion leads to dysfunction of motor and cognition via regulating glia-dependent neuronal migration during brain development. Cell Death Dis 2018; 9:999. [PMID: 30250269 PMCID: PMC6155261 DOI: 10.1038/s41419-018-1027-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 07/18/2018] [Indexed: 12/27/2022]
Abstract
The establishment of functional neuronal connectivity is dependent on the neuronal migration and the accurate positioning of neurons in the developing brain. Abnormal neuronal migration can trigger neuronal maturation defects and apoptosis. However, many genetic bases remain unclear in neuronal migration disorders during brain development. In this study, we reported that MARVELD1-defected mice displayed motor and cognitive dysfunction resulting from aberrant neuronal migration during brain development. The laminar organization of the cerebral cortex and cerebellum in MARVELD1 knockout (KO) mice is disrupted, indicating impaired radial neuronal migration. Furthermore, we used the cerebellum as a model to explore the radial neuronal migration processes, and the results demonstrated that the proper neuronal migration depended on MARVELD1 expression in glial cells of the developing brain. MARVELD1 suppressed the expression of ITGB1 and FAK Tyr397 phosphorylation in glia-dependent manner. The inhibition of the MARVELD1/ITGB1/FAK signalling pathway in MARVELD1 KO mice could reverse the defects in neuronal migration in vitro. Our findings revealed that MARVELD1 regulated neuronal migration by mediating the formation of glial fibres and ITGB1/FAK signalling pathway. The depletion of MARVELD1 during mouse brain development led to the abnormity of motor and cognition functions.
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35
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Walker RF. On the cause and mechanism of phenoptosis. BIOCHEMISTRY (MOSCOW) 2017; 82:1462-1479. [DOI: 10.1134/s0006297917120069] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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36
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Michel JJ, Griffin P, Vallejo AN. Functionally Diverse NK-Like T Cells Are Effectors and Predictors of Successful Aging. Front Immunol 2016; 7:530. [PMID: 27933066 PMCID: PMC5121286 DOI: 10.3389/fimmu.2016.00530] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 11/10/2016] [Indexed: 12/16/2022] Open
Abstract
The fundamental challenge of aging and long-term survivorship is maintenance of functional independence and compression of morbidity despite a life history of disease. Inasmuch as immunity is a determinant of individual health and fitness, unraveling novel mechanisms of immune homeostasis in late life is of paramount interest. Comparative studies of young and old persons have documented age-related atrophy of the thymus, the contraction of diversity of the T cell receptor (TCR) repertoire, and the intrinsic inefficiency of classical TCR signaling in aged T cells. However, the elderly have highly heterogeneous health phenotypes. Studies of defined populations of persons aged 75 and older have led to the recognition of successful aging, a distinct physiologic construct characterized by high physical and cognitive functioning without measurable disability. Significantly, successful agers have a unique T cell repertoire; namely, the dominance of highly oligoclonal αβT cells expressing a diverse array of receptors normally expressed by NK cells. Despite their properties of cell senescence, these unusual NK-like T cells are functionally active effectors that do not require engagement of their clonotypic TCR. Thus, NK-like T cells represent a beneficial remodeling of the immune repertoire with advancing age, consistent with the concept of immune plasticity. Significantly, certain subsets are predictors of physical/cognitive performance among older adults. Further understanding of the roles of these NK-like T cells to host defense, and how they integrate with other physiologic domains of function are new frontiers for investigation in Aging Biology. Such pursuits will require a research paradigm shift from the usual young-versus-old comparison to the analysis of defined elderly populations. These endeavors may also pave way to age-appropriate, group-targeted immune interventions for the growing elderly population.
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Affiliation(s)
- Joshua J Michel
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Patricia Griffin
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Abbe N Vallejo
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Pittsburgh Claude Pepper Older Americans Independence Center, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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da Costa JP, Vitorino R, Silva GM, Vogel C, Duarte AC, Rocha-Santos T. A synopsis on aging-Theories, mechanisms and future prospects. Ageing Res Rev 2016; 29:90-112. [PMID: 27353257 PMCID: PMC5991498 DOI: 10.1016/j.arr.2016.06.005] [Citation(s) in RCA: 205] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 06/23/2016] [Accepted: 06/23/2016] [Indexed: 12/31/2022]
Abstract
Answering the question as to why we age is tantamount to answering the question of what is life itself. There are countless theories as to why and how we age, but, until recently, the very definition of aging - senescence - was still uncertain. Here, we summarize the main views of the different models of senescence, with a special emphasis on the biochemical processes that accompany aging. Though inherently complex, aging is characterized by numerous changes that take place at different levels of the biological hierarchy. We therefore explore some of the most relevant changes that take place during aging and, finally, we overview the current status of emergent aging therapies and what the future holds for this field of research. From this multi-dimensional approach, it becomes clear that an integrative approach that couples aging research with systems biology, capable of providing novel insights into how and why we age, is necessary.
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Affiliation(s)
- João Pinto da Costa
- CESAM and Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
| | - Rui Vitorino
- Department of Medical Sciences, Institute for Biomedicine-iBiMED, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal; Department of Physiology and Cardiothoracic Surgery, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Gustavo M Silva
- Department of Biology, Center for Genomics and Systems Biology, NY, NY 10003, USA
| | - Christine Vogel
- Department of Biology, Center for Genomics and Systems Biology, NY, NY 10003, USA
| | - Armando C Duarte
- CESAM and Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - Teresa Rocha-Santos
- CESAM and Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
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38
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Mitteldorf J. An epigenetic clock controls aging. Biogerontology 2015; 17:257-65. [DOI: 10.1007/s10522-015-9617-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Accepted: 10/07/2015] [Indexed: 12/22/2022]
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von Wyschetzki K, Rueppell O, Oettler J, Heinze J. Transcriptomic Signatures Mirror the Lack of the Fecundity/Longevity Trade-Off in Ant Queens. Mol Biol Evol 2015; 32:3173-85. [PMID: 26341296 DOI: 10.1093/molbev/msv186] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Life-history theory predicts a trade-off between reproductive investment and self-maintenance. The negative association between fertility and longevity found throughout multicellular organisms supports this prediction. As an important exception, the reproductives of many eusocial insects (ants, bees, and termites) are simultaneously very long-lived and highly fertile. Here, we examine the proximate basis for this exceptional relationship by comparing whole-body transcriptomes of differently aged queens of the ant Cardiocondyla obscurior. We show that the sets of genes differentially expressed with age significantly overlap with age-related expression changes previously found in female Drosophila melanogaster. We identified several developmental processes, such as the generation of neurons, as common signatures of aging. More generally, however, gene expression in ant queens and flies changes with age mainly in opposite directions. In contrast to flies, reproduction-associated genes were upregulated and genes associated with metabolic processes and muscle contraction were downregulated in old relative to young ant queens. Furthermore, we searched for putative C. obscurior longevity candidates associated with the previously reported lifespan-prolonging effect of mating by comparing the transcriptomes of queens that differed in mating and reproductive status. We found 21 genes, including the putative aging candidate NLaz (an insect homolog of APOD), which were consistently more highly expressed in short-lived, unmated queens than in long-lived, mated queens. Our study provides clear evidence that the alternative regulation of conserved molecular pathways that mediate the interplay among mating, egg laying, and aging underlies the lack of the fecundity/longevity trade-off in ant queens.
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Affiliation(s)
| | - Olav Rueppell
- Department of Biology, University of North Carolina, Greensboro
| | - Jan Oettler
- LS Zoologie/Evolutionsbiologie, Universität Regensburg, Regensburg, Germany
| | - Jürgen Heinze
- LS Zoologie/Evolutionsbiologie, Universität Regensburg, Regensburg, Germany
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40
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A common brain network links development, aging, and vulnerability to disease. Proc Natl Acad Sci U S A 2014; 111:17648-53. [PMID: 25422429 DOI: 10.1073/pnas.1410378111] [Citation(s) in RCA: 203] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Several theories link processes of development and aging in humans. In neuroscience, one model posits for instance that healthy age-related brain degeneration mirrors development, with the areas of the brain thought to develop later also degenerating earlier. However, intrinsic evidence for such a link between healthy aging and development in brain structure remains elusive. Here, we show that a data-driven analysis of brain structural variation across 484 healthy participants (8-85 y) reveals a largely--but not only--transmodal network whose lifespan pattern of age-related change intrinsically supports this model of mirroring development and aging. We further demonstrate that this network of brain regions, which develops relatively late during adolescence and shows accelerated degeneration in old age compared with the rest of the brain, characterizes areas of heightened vulnerability to unhealthy developmental and aging processes, as exemplified by schizophrenia and Alzheimer's disease, respectively. Specifically, this network, while derived solely from healthy subjects, spatially recapitulates the pattern of brain abnormalities observed in both schizophrenia and Alzheimer's disease. This network is further associated in our large-scale healthy population with intellectual ability and episodic memory, whose impairment contributes to key symptoms of schizophrenia and Alzheimer's disease. Taken together, our results suggest that the common spatial pattern of abnormalities observed in these two disorders, which emerge at opposite ends of the life spectrum, might be influenced by the timing of their separate and distinct pathological processes in disrupting healthy cerebral development and aging, respectively.
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41
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DAF-16/FOXO and EGL-27/GATA promote developmental growth in response to persistent somatic DNA damage. Nat Cell Biol 2014; 16:1168-1179. [PMID: 25419847 PMCID: PMC4250074 DOI: 10.1038/ncb3071] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 10/22/2014] [Indexed: 12/16/2022]
Abstract
Genome maintenance defects cause complex disease phenotypes characterized by developmental failure, cancer susceptibility, and premature aging. It remains poorly understood how DNA damage responses function during organismal development and maintain tissue functionality when DNA damage accumulates with aging. Here we show that the FoxO transcription factor DAF-16 is activated in response to DNA damage during development while the DNA damage responsiveness of DAF-16 declines with aging. We find that in contrast to its established role in mediating starvation arrest, DAF-16 alleviates DNA damage-induced developmental arrest and even in the absence of DNA repair promotes developmental growth and enhances somatic tissue functionality. We demonstrate that the GATA transcription factor EGL-27 co-regulates DAF-16 target genes in response to DNA damage and together with DAF-16 promotes developmental growth. We propose that EGL-27/GATA activity specifies DAF-16 mediated DNA damage responses to enable developmental progression and to prolong tissue functioning when DNA damage persists.
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Abstract
Aging is marked by changes that affect organs and resident stem cell function. Shorting of telomeres, DNA damage, oxidative stress, deregulation of genes and proteins, impaired cell-cell communication, and an altered systemic environment cause the eventual demise of cells. At the same time, reparative activities also decline. It is intriguing to correlate aging with the decline of regenerative abilities. Animal models with strong regenerative capabilities imply that aging processes might not be affecting regeneration. In this review, we selectively present age-dependent changes in stem/progenitor cells that are vital for tissue homeostasis and repair. In addition, the aging effect on regeneration following injury in organs such as lung, skeletal muscle, heart, nervous system, cochlear hair, lens, and liver are discussed. These tissues are also known for diseases such as heart attack, stroke, cognitive impairment, cataract, and hearing loss that occur mostly during aging in humans. Conclusively, vertebrate regeneration declines with age with the loss of stem/progenitor cell function. Future studies on improving the function of stem cells, along with studies in fish and amphibians where regeneration does not decline with age, will undoubtedly provide insights into both processes.
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Affiliation(s)
- Konstantinos Sousounis
- Department of Biology and Center for Tissue Regeneration and Engineering, University of Dayton, Dayton, Ohio, USA
| | - Joelle A Baddour
- Department of Chemical and Materials Engineering and Center for Tissue Regeneration and Engineering, University of Dayton, Dayton, Ohio, USA
| | - Panagiotis A Tsonis
- Department of Biology and Center for Tissue Regeneration and Engineering, University of Dayton, Dayton, Ohio, USA.
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43
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Affiliation(s)
- Robert L Chevalier
- Division of Pediatric Nephrology, Department of Pediatrics, University of Virginia, Charlottesville, Virginia
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Kulminski AM. Unraveling genetic origin of aging-related traits: evolving concepts. Rejuvenation Res 2014; 16:304-12. [PMID: 23768105 DOI: 10.1089/rej.2013.1441] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Discovering the genetic origin of aging-related traits could greatly advance strategies aiming to extend health span. The results of genome-wide association studies (GWAS) addressing this problem are controversial, and new genetic concepts have been fostered to advance the progress in the field. A limitation of GWAS and new genetic concepts is that they do not thoroughly address specifics of aging-related traits. Integration of theoretical concepts in genetics and aging research with empirical evidence from different disciplines highlights the conceptual problems in studies of genetic origin of aging-related traits. To address these problems, novel approaches of systemic nature are required. These approaches should adopt the non-deterministic nature of linkage of genes with aging-related traits and, consequently, reinforce research strategies for improving our understanding of mechanisms shaping genetic effects on these traits. Investigation of mechanisms will help determine conditions that activate specific genetic variants or profiles and explore to what extent these conditions that shape genetic effects are conserved across human lives and generations.
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Affiliation(s)
- Alexander M Kulminski
- Center for Population Health and Aging, Duke University, Durham, North Carolina 27708, USA.
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Wnuk M, Lewinska A, Gurgul A, Zabek T, Potocki L, Oklejewicz B, Bugno-Poniewierska M, Wegrzyn M, Slota E. Changes in DNA methylation patterns and repetitive sequences in blood lymphocytes of aged horses. AGE (DORDRECHT, NETHERLANDS) 2014; 36:31-48. [PMID: 23700175 PMCID: PMC3889908 DOI: 10.1007/s11357-013-9541-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Accepted: 05/06/2013] [Indexed: 05/13/2023]
Abstract
It is known that aged organisms have modified epigenomes. Epigenetic modifications, such as changes in global and locus-specific DNA methylation, and histone modifications are suspected to play an important role in cancer development and aging. In the present study, with the well-established horse aging model, we showed the global loss of DNA methylation in blood lymphocytes during juvenile-to-aged period. Additionally, we tested a pattern of DNA methylation of ribosomal DNA and selected genes such as IGF2 and found no significant changes during development and aging. We asked if genetic components such as polymorphisms within DNA methyltransferase genes, DNMT1, DNMT3a, and DNMT3b, may contribute to observed changes in global DNA methylation status. The analysis of seven intragenic polymorphisms did not reveal any significant association with changes in global DNA methylation. Telomere shortage and a loss of pericentromeric heterochromatin during juvenile-to-aged period were also observed. Transcriptional rDNA activity, assessed as the number and size of nucleolar organizer regions, reflecting physiological state of the cell, and mitotic index were decreased with increasing horse donor age. Moreover, changes during juvenile-to-aged period and adult-to-aged period were compared and discussed. Taken together, changes in global DNA methylation status originating in development and affecting the stability of repetitive sequences may be associated with previously reported genomic instability during horse aging.
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Affiliation(s)
- Maciej Wnuk
- Department of Genetics, University of Rzeszów, Rejtana 16C, PL 35-959, Rzeszów, Poland,
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Neill D. Life's timekeeper. Ageing Res Rev 2013; 12:567-78. [PMID: 23354279 DOI: 10.1016/j.arr.2013.01.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Revised: 01/08/2013] [Accepted: 01/10/2013] [Indexed: 12/18/2022]
Abstract
Life's timekeeper is a 'free-running' intracellular oscillator synchronised across all cells. It runs throughout life splitting lifespan into equal length phases. During the maturational period it controls the overall rate of progression whereas in the post-maturational period it controls the overall rate of ageing. This includes the rate of senescence and hence time to death. As such life's timekeeper equates maturational and post-maturational time, hence explains the tight correlation between these time periods that has existed throughout mammalian evolution. Life's timekeeper is proposed to have played an important role in vertebrate evolution. A slower oscillatory frequency results in proportional life phase prolongation. This leads to increased body and brain size, together with extended lifespan. Higher brain centres, neocortex in mammals, are disproportionately enlarged. Hence behavioural capacity is increased. The extended post-maturational period ensures that there is enough time in order that the behavioural advantages can be fully manifest in the environment. A faster oscillatory frequency would result in proportional life phase reduction. This process however would lead to reduced behavioural capacity, and is hence unlikely to be positively selected. Therefore throughout evolution life's timekeeper has operated to extend lifespan. It has hence functioned to promote longevity as opposed to ageing.
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Affiliation(s)
- David Neill
- Department of Psychiatry, Newcastle University, Newcastle Upon Tyne NE1 7RU, United Kingdom.
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Abstract
The TP53 gene, first described in 1979, was identified as a tumor suppressor gene in 1989, when it became clear that its product, the p53 nuclear phosphoprotein, was frequently inactivated in many different forms of cancers. Nicknamed "guardian of the genome", TP53 occupies a central node in stress response networks. The p53 protein has a key role as transcription factor in limiting oncogenesis through several growth suppressive functions, such as initiating apoptosis, senescence, or cell cycle arrest. The p53 protein is directly inactivated in about 50% of all tumors as a result of somatic gene mutations or deletions, and over 80% of tumors demonstrate dysfunctional p53 signaling. Beyond the undeniable importance of p53 as a tumor suppressor, an increasing number of new functions for p53 have been reported, including its ability to regulate energy metabolism, to control autophagy, and to participate in various aspects of differentiation and development. Recently, studies on genetic variations in TP53 among different populations have led to the notion that the p53 protein might play an important role in regulating fertility. This review summarizes current knowledge on the basic functions of different genes of the TP53 family and TP53 pathway with respect to fertility. We also provide original analyses based on genomic and genotype databases, providing further insights into the possible roles of the TP53 pathway in human reproduction.
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Affiliation(s)
- Diego d'Avila Paskulin
- Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. ; Laboratório de Medicina Genômica, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil
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Naumova OY, Lee M, Rychkov SY, Vlasova NV, Grigorenko EL. Gene expression in the human brain: the current state of the study of specificity and spatiotemporal dynamics. Child Dev 2012; 84:76-88. [PMID: 23145569 DOI: 10.1111/cdev.12014] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Gene expression is one of the main molecular processes regulating the differentiation, development, and functioning of cells and tissues. In this review a handful of relevant terms and concepts are introduced and the most common techniques used in studies of gene expression/expression profiling (also referred to as studies of the transcriptome or transcriptomics) are described. The main foci of this review are the advancements in studies of the transcriptome in the human brain, the transcriptome's variability across different brain structures, and the systematic changes that occur through different developmental stages across the life span in general and childhood in particular. Finally, the question of how the accumulating data on the spatial and temporal dynamics of the transcriptome may shed light on the molecular mechanisms of the typical and atypical development of the central nervous system is addressed.
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Tacutu R, Shore DE, Budovsky A, de Magalhães JP, Ruvkun G, Fraifeld VE, Curran SP. Prediction of C. elegans longevity genes by human and worm longevity networks. PLoS One 2012; 7:e48282. [PMID: 23144747 PMCID: PMC3483217 DOI: 10.1371/journal.pone.0048282] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 09/21/2012] [Indexed: 11/18/2022] Open
Abstract
Intricate and interconnected pathways modulate longevity, but screens to identify the components of these pathways have not been saturating. Because biological processes are often executed by protein complexes and fine-tuned by regulatory factors, the first-order protein-protein interactors of known longevity genes are likely to participate in the regulation of longevity. Data-rich maps of protein interactions have been established for many cardinal organisms such as yeast, worms, and humans. We propose that these interaction maps could be mined for the identification of new putative regulators of longevity. For this purpose, we have constructed longevity networks in both humans and worms. We reasoned that the essential first-order interactors of known longevity-associated genes in these networks are more likely to have longevity phenotypes than randomly chosen genes. We have used C. elegans to determine whether post-developmental inactivation of these essential genes modulates lifespan. Our results suggest that the worm and human longevity networks are functionally relevant and possess a high predictive power for identifying new longevity regulators.
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Affiliation(s)
- Robi Tacutu
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Center for Multidisciplinary Research on Aging, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - David E. Shore
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Arie Budovsky
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Center for Multidisciplinary Research on Aging, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - João Pedro de Magalhães
- Integrative Genomics of Ageing Group, Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Gary Ruvkun
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Vadim E. Fraifeld
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Center for Multidisciplinary Research on Aging, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- * E-mail: (VEF); (SPC)
| | - Sean P. Curran
- Division of Biogerontology, Davis School of Gerontology, University of Southern California, Los Angeles, California, United States of America
- Department of Molecular and Computational Biology, Dornsife College of Letters, Arts, and Sciences, University of Southern California, Los Angeles, California, United States of America
- Department of Biochemistry and Molecular Biology, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
- * E-mail: (VEF); (SPC)
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de Magalhães JP. Programmatic features of aging originating in development: aging mechanisms beyond molecular damage? FASEB J 2012; 26:4821-6. [PMID: 22964300 PMCID: PMC3509060 DOI: 10.1096/fj.12-210872] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The idea that aging follows a predetermined sequence of events, a program, has been discredited by most contemporary authors. Instead, aging is largely thought to occur due to the accumulation of various forms of molecular damage. Recent work employing functional genomics now suggests that, indeed, certain facets of mammalian aging may follow predetermined patterns encoded in the genome as part of developmental processes. It appears that genetic programs coordinating some aspects of growth and development persist into adulthood and may become detrimental. This link between development and aging may occur due to regulated processes, including through the action of microRNAs and epigenetic mechanisms. Taken together with other results, in particular from worms, these findings provide evidence that some aging changes are not primarily a result of a build-up of stochastic damage but are rather a product of regulated processes. These processes are interpreted as forms of antagonistic pleiotropy, the product of a “shortsighted watchmaker,” and thus do not assume aging evolved for a purpose. Overall, it appears that the genome does, indeed, contain specific instructions that drive aging in animals, a radical shift in our perception of the aging process.—de Magalhães, J. P. Programmatic features of aging originating in development: aging mechanisms beyond molecular damage?
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Affiliation(s)
- João Pedro de Magalhães
- Integrative Genomics of Ageing Group, Institute of Integrative Biology, University of Liverpool, Liverpool, UK.
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