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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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2
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Yang W, Xia W, Zheng B, Li T, Liu RH. DAF-16 is involved in colonic metabolites of ferulic acid-promoted longevity and stress resistance of Caenorhabditis elegans. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2022; 102:7017-7029. [PMID: 35689482 DOI: 10.1002/jsfa.12063] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 05/11/2022] [Accepted: 06/11/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Ferulic acid (FA) is a dietary polyphenol widely found in plant tissues. It has long been considered to have health-promoting qualities. However, the biological properties of dietary polyphenols depend largely on their absorption during digestion, and the effects of their intestinal metabolites on human health have attracted the interest of researchers. This study evaluated the effects of three main colonic metabolites of FA - 3-(3,4-dihydroxyphenyl)propionic acid (3,4diOHPPA), 3-(3-hydroxyphenyl)propionic acid (3OHPPA) and 3-phenylpropionic acid (3PPA) - on longevity and stress resistance in Caenorhabditis elegans. RESULTS Our results showed that 3,4diOHPPA, 3OHPPA and 3PPA extended the lifespan under normal conditions in C. elegans whereas FA did not. High doses of 3,4diOHPPA (0.5 mmol L-1 ), 3OHPPA (2.5 mmol L-1 ) and 3PPA (2.5 mmol L-1 ) prolonged the mean lifespan by 11.2%, 13.0% and 10.6%, respectively. Moreover, 3,4diOHPPA, 3OHPPA and 3PPA treatments promoted stress tolerance against heat, UV irradiation and paraquat. Furthermore, three metabolites ameliorated physical functions, including reactive oxygen species and malondialdehyde levels, motility and pharyngeal pumping rate. The anti-aging activities mediated by 3,4diOHPPA, 3OHPPA and 3PPA depend on the HSF-1 and JNK-1 linked insulin/IGF-1 signaling pathway, which converge onto DAF-16. CONCLUSION The current findings suggest that colonic metabolites of FA have the potential for use as anti-aging bioactivate compounds. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Wenhan Yang
- Overseas Expertise Introduction Center for Discipline Innovation of Food Nutrition and Human Health (111 Center), School of Food Science and Engineering, South China University of Technology, Guangzhou, China
| | - Wen Xia
- Overseas Expertise Introduction Center for Discipline Innovation of Food Nutrition and Human Health (111 Center), School of Food Science and Engineering, South China University of Technology, Guangzhou, China
| | - Bisheng Zheng
- Overseas Expertise Introduction Center for Discipline Innovation of Food Nutrition and Human Health (111 Center), School of Food Science and Engineering, South China University of Technology, Guangzhou, China
- Guangdong ERA Food and Life Health Research Institute, Guangzhou, China
| | - Tong Li
- Department of Food Science, Cornell University, Ithaca, New York, USA
| | - Rui Hai Liu
- Department of Food Science, Cornell University, Ithaca, New York, USA
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Raj Kolora SR, Owens GL, Vazquez JM, Stubbs A, Chatla K, Jainese C, Seeto K, McCrea M, Sandel MW, Vianna JA, Maslenikov K, Bachtrog D, Orr JW, Love M, Sudmant PH. Origins and evolution of extreme life span in Pacific Ocean rockfishes. Science 2021; 374:842-847. [PMID: 34762458 PMCID: PMC8923369 DOI: 10.1126/science.abg5332] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Pacific Ocean rockfishes (genus Sebastes) exhibit extreme variation in life span, with some species being among the most long-lived extant vertebrates. We de novo assembled the genomes of 88 rockfish species and from these identified repeated signatures of positive selection in DNA repair pathways in long-lived taxa and 137 longevity-associated genes with direct effects on life span through insulin signaling and with pleiotropic effects through size and environmental adaptations. A genome-wide screen of structural variation reveals copy number expansions in the immune modulatory butyrophilin gene family in long-lived species. The evolution of different rockfish life histories is coupled to genetic diversity and reshapes the mutational spectrum driving segregating CpG→TpG variants in long-lived species. These analyses highlight the genetic innovations that underlie life history trait adaptations and, in turn, how they shape genomic diversity.
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Affiliation(s)
| | - Gregory L. Owens
- University of California Berkeley Department of Integrative Biology
- University of Victoria Department of Biology
| | | | - Alexander Stubbs
- University of California Berkeley Department of Integrative Biology
| | - Kamalakar Chatla
- University of California Berkeley Department of Integrative Biology
| | - Conner Jainese
- University of California Santa Barbara Marine Sciences Institute
| | - Katelin Seeto
- University of California Santa Barbara Marine Sciences Institute
| | - Merit McCrea
- University of California Santa Barbara Marine Sciences Institute
| | | | - Juliana A. Vianna
- Pontificia Universidad Católica de Chile, Departamento de Ecosistemas y Medio Ambiente
| | - Katherine Maslenikov
- University of Washington, School of Aquatic and Fishery Sciences and Burke Museum of Natural History and Culture
| | - Doris Bachtrog
- University of California Berkeley Department of Integrative Biology
| | - James W. Orr
- University of Washington, School of Aquatic and Fishery Sciences and Burke Museum of Natural History and Culture
| | - Milton Love
- University of California Santa Barbara Marine Sciences Institute
| | - Peter H. Sudmant
- University of California Berkeley Department of Integrative Biology
- University of California Berkeley Center for Computational Biology
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Abstract
Aging occurs in all sexually reproducing organisms. That is, physical degradation over time occurs from conception until death. While the life span of a species is often viewed as a benchmark of aging, the pace and intensity of physical degradation over time varies owing to environmental influences, genetics, allocation of energetic investment, and phylogenetic history. Significant variation in aging within mammals, primates, and great apes, including humans, is therefore common across species. The evolution of aging in the hominin lineage is poorly known; however, clues can be derived from the fossil record. Ongoing advances continue to shed light on the interactions between life-history variables such as reproductive effort and aging. This review presents our current understanding of the evolution of aging in humans, drawing on population variation, comparative research, trade-offs, and sex differences, as well as tissue-specific patterns of physical degradation. Implications for contemporary health challenges and the future of human evolutionary anthropology research are also discussed.
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Abstract
Abstract
Ageing is distinct from a disease. Sound arguments have been adduced to explain that senescence cannot be understood as a pathological process. Nevertheless, this distinction is believed to be artificial (Holliday 1995), and other eminent researchers argue that the senescence-pathology dichotomy is also misleading. Recently, it has been suggested that ageing should be classified as a complex pathological syndrome or a ‘pre-disease’ that is treatable. Proponents of this new paradigm argue that: (i) modern evolutionary theory predicts that ‘although organismal senescence is not an adaptation, it is genetically programmed’, (ii) ‘insofar as it is genetically determined, organismal senescence is a form of genetic disease’ (Janac et al. 2017) and (iii) ‘ageing is something very much like a genetic disease: it is a set of pathologies resulting from the action of pleiotropic gene mutations’ (Gems 2015). Also new generations of researchers, free of these traditional shackles, come with the belief that it is time to classify ageing as a disease, as the distinction between normal dysfunction and abnormal dysfunction is not completely clear and should be abandoned. Although they marshal their arguments in a convincing manner, persuasive counterarguments can be mounted. Here, the senescence-pathology dichotomy is critically discussed. A deeper analysis of this subject reveals the underlying problem of undefined terminology in science.
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Frankish CK, Manica A, Phillips RA. Effects of age on foraging behavior in two closely related albatross species. MOVEMENT ECOLOGY 2020; 8:7. [PMID: 32047635 PMCID: PMC7006180 DOI: 10.1186/s40462-020-0194-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 01/23/2020] [Indexed: 06/10/2023]
Abstract
BACKGROUND Foraging performance is widely hypothesized to play a key role in shaping age-specific demographic rates in wild populations, yet the underlying behavioral changes are poorly understood. Seabirds are among the longest-lived vertebrates, and demonstrate extensive age-related variation in survival, breeding frequency and success. The breeding season is a particularly critical phase during the annual cycle, but it remains unclear whether differences in experience or physiological condition related to age interact with the changing degree of the central-place constraint in shaping foraging patterns in time and space. METHODS Here we analyze tracking data collected over two decades from congeneric black-browed (BBA) and grey-headed (GHA) albatrosses, Thalassarche melanophris and T. chrysostoma, breeding at South Georgia. We compare the foraging trip parameters, at-sea activity (flights and landings) and habitat preferences of individuals aged 10-45 years and contrast these patterns between the incubation and early chick-rearing stages. RESULTS Young breeders of both species showed improvements in foraging competency with age, reducing foraging trip duration until age 26. Thereafter, there were signs of foraging senescence; older adults took gradually longer trips, narrowed their habitat preference (foraging within a smaller range of sea surface temperatures) (GHA), made fewer landings and rested on the water for longer (BBA). Some age-specific effects were apparent for each species only in certain breeding stages, highlighting the complex interaction between intrinsic drivers in determining individual foraging strategies. CONCLUSIONS Using cross-sectional data, this study highlighted clear age-related patterns in foraging behavior at the population-level for two species of albatrosses. These trends are likely to have important consequences for the population dynamics of these threatened seabirds, as young or old individuals may be more vulnerable to worsening environmental conditions.
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Affiliation(s)
- Caitlin K. Frankish
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET UK
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ UK
| | - Andrea Manica
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ UK
| | - Richard A. Phillips
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET UK
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Chmielewski PP. Human ageing as a dynamic, emergent and malleable process: from disease-oriented to health-oriented approaches. Biogerontology 2019; 21:125-130. [PMID: 31595371 PMCID: PMC6942601 DOI: 10.1007/s10522-019-09839-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 09/28/2019] [Indexed: 12/22/2022]
Abstract
Over the decades, biogerontology has matured as a scientific discipline. Currently, a number of theoretical frameworks are available to researchers when interpreting empirical data. Despite the great progress that has been made, a comprehensive understanding of biological processes that shape ageing is lacking. Senescence is a dynamic, plastic and highly complex metaphenomenon whose aetiology remains unclear. The paucity of information notwithstanding, some researchers promote ‘anti-ageing’ drugs and formulae every now and again. The rationale behind this concept is that ageing can be reduced to a mixture of biochemical reactions. Furthermore, the distinction between ageing and disease has been questioned on the grounds that ageing is the root of age-related diseases. It has been claimed that disease-oriented approaches can help delay ageing and prevent age-related diseases. Although these methods seem incongruous from an evolutionary standpoint, they become popular amongst the public. Moreover, if ageing is classified as a disease, this situation is likely to be exacerbated. Therefore, it is important to recognise the limitations of these reductionist and disease-oriented approaches. Only holistic and evidence-based strategies might be useful in slowing down ageing and preventing age-related diseases in the future.
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Affiliation(s)
- Piotr Paweł Chmielewski
- Division of Anatomy, Department of Human Morphology and Embryology, Faculty of Medicine, Wroclaw Medical University, 6a Chałubińskiego Street, 50-368, Wrocław, Poland.
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Palau Daval N, Gardette V, Joly P. Age, courtship and senescence: sexual ornaments are larger in older great crested newts. J Zool (1987) 2018. [DOI: 10.1111/jzo.12579] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- N. Palau Daval
- UMR 5023 LEHNA Lyon1, CNRS, ENTPE Université de Lyon Villeurbanne France
| | - V. Gardette
- UMR 5023 LEHNA Lyon1, CNRS, ENTPE Université de Lyon Villeurbanne France
| | - P. Joly
- UMR 5023 LEHNA Lyon1, CNRS, ENTPE Université de Lyon Villeurbanne France
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Yadav JP, Singh P. Effect of metabolites on stress, adaptation and longevity in laboratory populations of
Drosophila
flies. J Zool (1987) 2018. [DOI: 10.1111/jzo.12535] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- J. P. Yadav
- Department of Zoology Bundelkhand University Jhansi India
| | - P. Singh
- Department of Zoology Bundelkhand University Jhansi India
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O'Toole PW, Jeffery IB. Microbiome-health interactions in older people. Cell Mol Life Sci 2018; 75:119-128. [PMID: 28986601 PMCID: PMC11105677 DOI: 10.1007/s00018-017-2673-z] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 09/29/2017] [Indexed: 02/07/2023]
Abstract
Alterations in the composition and function of the gut microbiome have been implicated in a range of conditions and diseases. Culture-dependent and culture-independent studies both showed that older people harbour a gut microbiome that differs in composition from that of younger adults. Detailed analyses have identified discrete microbiota subtypes that characterize intermediates between a high diversity microbiota found in healthy community-dwelling subjects and a low diversity microbiota typical for elderly living in long-term residential care. There are also alterations in the microbiome composition associated with biological age, independent of health status. Even after adjusting for confounding factors such as age and medication, trends in microbiota composition correlate with gradients in clinical metadata particularly frailty and inflammatory status. There are few known mechanisms by which these associations might be causative rather than consequential, and this is a subject of intensive research. The strongest candidate effectors are microbial metabolites that could impact host energy balance, act as signalling molecules to modulate host metabolism or inflammation, and potentially also impact on the gut-brain axis.
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Affiliation(s)
- Paul W O'Toole
- School of Microbiology and APC Microbiome Institute, University College Cork, Cork, T12 YN60, Ireland.
| | - Ian B Jeffery
- School of Microbiology and APC Microbiome Institute, University College Cork, Cork, T12 YN60, Ireland
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Abstract
Current theories attribute aging to a failure of selection, due to either pleiotropic constraints or declining strength of selection after the onset of reproduction. These theories implicitly leave open the possibility that if senescence-causing alleles could be identified, or if antagonistic pleiotropy could be broken, the effects of aging might be ameliorated or delayed indefinitely. These theories are built on models of selection between multicellular organisms, but a full understanding of aging also requires examining the role of somatic selection within an organism. Selection between somatic cells (i.e., intercellular competition) can delay aging by purging nonfunctioning cells. However, the fitness of a multicellular organism depends not just on how functional its individual cells are but also on how well cells work together. While intercellular competition weeds out nonfunctional cells, it may also select for cells that do not cooperate. Thus, intercellular competition creates an inescapable double bind that makes aging inevitable in multicellular organisms.
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Cheynel L, Lemaître JF, Gaillard JM, Rey B, Bourgoin G, Ferté H, Jégo M, Débias F, Pellerin M, Jacob L, Gilot-Fromont E. Immunosenescence patterns differ between populations but not between sexes in a long-lived mammal. Sci Rep 2017; 7:13700. [PMID: 29057949 PMCID: PMC5651810 DOI: 10.1038/s41598-017-13686-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 09/22/2017] [Indexed: 11/08/2022] Open
Abstract
In animals, physiological mechanisms underlying reproductive and actuarial senescence remain poorly understood. Immunosenescence, the decline in the ability to display an efficient immune response with increasing age, is likely to influence both reproductive and actuarial senescence through increased risk of disease. Evidence for such a link has been reported from laboratory animal models but has been poorly investigated in the wild, where variation in resource acquisitions usually drives life-history trade-offs. We investigated immunosenescence patterns over 7 years in both sexes of two contrasting roe deer populations (Capreolus capreolus). We first measured twelve immune markers to obtain a thorough identification of innate and adaptive components of immunity and assessed, from the same individuals, the age-dependent variation observed in parasitic infections. Although the level of innate traits was maintained at old age, the functional innate immune traits declined with increasing age in one of two populations. In both populations, the production of inflammatory markers increased with advancing age. Finally, the adaptive response declined in late adulthood. The increasing parasite burden with age we reported suggests the effective existence of immunosenescence. Age-specific patterns differed between populations but not between sexes, which indicate that habitat quality could shape age-dependent immune phenotype in the wild.
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Affiliation(s)
- L Cheynel
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France.
| | - J-F Lemaître
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
| | - J-M Gaillard
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
| | - B Rey
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
| | - G Bourgoin
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
- Université de Lyon, VetAgro Sup, Marcy-l'Etoile, France
| | - H Ferté
- EA 4688 "VECPAR", UFR Pharmacie, Université de Reims Champagne-Ardenne, Reims, France
| | - M Jégo
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
| | - F Débias
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
| | - M Pellerin
- Office National de la Chasse et de la Faune Sauvage, Centre National de Recherches Appliquées sur les Cervidés-Sanglier, Bar-le-Duc, France
| | - L Jacob
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
| | - E Gilot-Fromont
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
- Université de Lyon, VetAgro Sup, Marcy-l'Etoile, France
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Pietrzak B, Dawidowicz P, Prędki P, Dańko MJ. How perceived predation risk shapes patterns of aging in water fleas. Exp Gerontol 2015; 69:1-8. [DOI: 10.1016/j.exger.2015.05.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 04/19/2015] [Accepted: 05/14/2015] [Indexed: 01/31/2023]
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Hau M, Haussmann MF, Greives TJ, Matlack C, Costantini D, Quetting M, Adelman JS, Miranda AC, Partecke J. Repeated stressors in adulthood increase the rate of biological ageing. Front Zool 2015; 12:4. [PMID: 25705242 PMCID: PMC4336494 DOI: 10.1186/s12983-015-0095-z] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 01/12/2015] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Individuals of the same age can differ substantially in the degree to which they have accumulated tissue damage, akin to bodily wear and tear, from past experiences. This accumulated tissue damage reflects the individual's biological age and may better predict physiological and behavioural performance than the individual's chronological age. However, at present it remains unclear how to reliably assess biological age in individual wild vertebrates. METHODS We exposed hand-raised adult Eurasian blackbirds (Turdus merula) to a combination of repeated immune and disturbance stressors for over one year to determine the effects of chronic stress on potential biomarkers of biological ageing including telomere shortening, oxidative stress load, and glucocorticoid hormones. We also assessed general measures of individual condition including body mass and locomotor activity. RESULTS By the end of the experiment, stress-exposed birds showed greater decreases in telomere lengths. Stress-exposed birds also maintained higher circulating levels of oxidative damage compared with control birds. Other potential biomarkers such as concentrations of antioxidants and glucocorticoid hormone traits showed greater resilience and did not differ significantly between treatment groups. CONCLUSIONS The current data demonstrate that repeated exposure to experimental stressors affects the rate of biological ageing in adult Eurasian blackbirds. Both telomeres and oxidative damage were affected by repeated stress exposure and thus can serve as blood-derived biomarkers of biological ageing.
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Affiliation(s)
- Michaela Hau
- Max Planck Institute for Ornithology, Evolutionary Physiology Group, Am Obstberg 1, 78315 Radolfzell, Germany ; Department of Biology, University of Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany
| | - Mark F Haussmann
- Department of Biology, Bucknell University, Lewisburg, PA 17837 USA
| | - Timothy J Greives
- Max Planck Institute for Ornithology, Evolutionary Physiology Group, Am Obstberg 1, 78315 Radolfzell, Germany ; Department of Biological Sciences, North Dakota State University, 1340 Bolley Drive, Fargo, ND 58202 USA
| | - Christa Matlack
- Department of Biology, Bucknell University, Lewisburg, PA 17837 USA
| | - David Costantini
- Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium ; University of Glasgow, Institute of Biodiversity, Animal Health & Comparative Medicine, Glasgow, QG12 8Q UK
| | - Michael Quetting
- Max Planck Institute for Ornithology, Evolutionary Physiology Group, Am Obstberg 1, 78315 Radolfzell, Germany ; Department of Biology, University of Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany
| | - James S Adelman
- Max Planck Institute for Ornithology, Evolutionary Physiology Group, Am Obstberg 1, 78315 Radolfzell, Germany ; Department of Biological Sciences, 4092B Derring Hall, Virginia Tech, Blacksburg, VA 24061-0406 USA
| | - Ana Catarina Miranda
- Department of Biology, University of Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany ; Max Planck Institute for Ornithology, Department of Migration and Immuno-ecology, Am Obstberg 1, 78315 Radolfzell, Germany ; Departamento de Biologia, Centro de Ciências Biológicas e da Saúde, Universidade Federal do Maranhão, Campus do Bacanga, São Luís, Maranhão Brazil
| | - Jesko Partecke
- Department of Biology, University of Konstanz, Universitätsstraße 10, 78464 Konstanz, Germany ; Max Planck Institute for Ornithology, Department of Migration and Immuno-ecology, Am Obstberg 1, 78315 Radolfzell, Germany
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Wensink MJ, Wrycza TF, Baudisch A. Interaction mortality: senescence may have evolved because it increases lifespan. PLoS One 2014; 9:e109638. [PMID: 25299047 PMCID: PMC4192302 DOI: 10.1371/journal.pone.0109638] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 09/07/2014] [Indexed: 01/13/2023] Open
Abstract
Given an extrinsic challenge, an organism may die or not depending on how the threat interacts with the organism's physiological state. To date, such interaction mortality has been only a minor factor in theoretical modeling of senescence. We describe a model of interaction mortality that does not involve specific functions, making only modest assumptions. Our model distinguishes explicitly between the physiological state of an organism and potential extrinsic, age-independent threats. The resulting mortality may change with age, depending on whether the organism's state changes with age. We find that depending on the physiological constraints, any outcome, be it 'no senescence' or 'high rate of senescence', can be found in any environment; that the highest optimal rate of senescence emerges for an intermediate physiological constraint, i.e. intermediate strength of trade-off; and that the optimal rate of senescence as a function of the environment is driven by the way the environment changes the effect of the organism's state on mortality. We conclude that knowledge about the environment, physiology and their interaction is necessary before reasonable predictions about the evolution of senescence can be made.
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Affiliation(s)
- Maarten J. Wensink
- Max Planck Research Group 'Modeling the Evolution of Aging, Max Planck Institute for Demographic Research, Rostock, Germany
- Leyden Academy on Vitality and Ageing, Leiden, The Netherlands
- * E-mail:
| | - Tomasz F. Wrycza
- Max Planck Research Group 'Modeling the Evolution of Aging, Max Planck Institute for Demographic Research, Rostock, Germany
| | - Annette Baudisch
- Max Planck Research Group 'Modeling the Evolution of Aging, Max Planck Institute for Demographic Research, Rostock, Germany
- Max-Planck Odense Center on the Biodemography of Aging, University of Southern Denmark, Odense M, Denmark
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Kraus C, Pavard S, Promislow DEL. The size-life span trade-off decomposed: why large dogs die young. Am Nat 2013; 181:492-505. [PMID: 23535614 DOI: 10.1086/669665] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Large body size is one of the best predictors of long life span across species of mammals. In marked contrast, there is considerable evidence that, within species, larger individuals are actually shorter lived. This apparent cost of larger size is especially evident in the domestic dog, where artificial selection has led to breeds that vary in body size by almost two orders of magnitude and in average life expectancy by a factor of two. Survival costs of large size might be paid at different stages of the life cycle: a higher early mortality, an early onset of senescence, an elevated baseline mortality, or an increased rate of aging. After fitting different mortality hazard models to death data from 74 breeds of dogs, we describe the relationship between size and several mortality components. We did not find a clear correlation between body size and the onset of senescence. The baseline hazard is slightly higher in large dogs, but the driving force behind the trade-off between size and life span is apparently a strong positive relationship between size and aging rate. We conclude that large dogs die young mainly because they age quickly.
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Affiliation(s)
- Cornelia Kraus
- Laboratory of Survival and Longevity, Max Planck Institute for Demographic Research, Rostock, Germany.
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Thomas H. Senescence, ageing and death of the whole plant. THE NEW PHYTOLOGIST 2013; 197:696-711. [PMID: 23176101 DOI: 10.1111/nph.12047] [Citation(s) in RCA: 244] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 10/15/2012] [Indexed: 05/18/2023]
Abstract
UNLABELLED 696 I. 697 II. 697 III. 699 IV. 700 V. 703 VI. 704 VII. 707 708 References 708 SUMMARY This review considers the relationship between the lifespan of an individual plant and the longevity of its component cells, tissues and organs. It begins by defining the terms senescence, growth, development, turnover, ageing, death and program. Genetic and epigenetic mechanisms regulating phase change from juvenility to maturity influence directly the capacity for responding to senescence signals and factors determining reproduction-related patterns of deteriorative ageing and death. Senescence is responsive to communication between sources and sinks in which sugar signalling and hormonal regulation play central roles. Monocarpy and polycarpy represent contrasting outcomes of the balance between the determinacy of apical meristems and source-sink cross-talk. Even extremely long-lived perennials sustain a high degree of meristem integrity. Factors associated with deteriorative ageing in animals, such as somatic mutation, telomere attrition and the costs of repair and maintenance, do not seem to be particularly significant for plant lifespan, but autophagy-related regulatory networks integrated with nutrient signalling may have a part to play. Size is an important influence on physiological function and fitness of old trees. Self-control of modular structure allows trees to sustain viability over prolonged lifespans. Different turnover patterns of structural modules can account for the range of plant life histories and longevities.
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Affiliation(s)
- Howard Thomas
- IBERS, Aberystwyth University, Edward Llwyd Building, Aberystwyth, Ceredigion, SY23 3DA, UK
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Hettyey A, Vági B, Penn DJ, Hoi H, Wagner RH. Post-meiotic intra-testicular sperm senescence in a wild vertebrate. PLoS One 2012; 7:e50820. [PMID: 23226542 PMCID: PMC3513296 DOI: 10.1371/journal.pone.0050820] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 10/29/2012] [Indexed: 11/24/2022] Open
Abstract
There is growing interest in sperm senescence, both in its underlying mechanisms and evolutionary consequences, because it can impact the evolution of numerous life history traits. Previous studies have documented various types of sperm senescence, but evidence of post-meiotic intra-testicular sperm senescence in wild animals is lacking. To assess such senescence, we studied within-season changes in sperm motility in the common toad (Bufo bufo), where males produce all sperm prior to the breeding season. We found that males exposed to experimentally induced re-hibernation at the start of the breeding season, that is to experimentally lowered metabolic rates, stored sperm of significantly higher motility than males that were kept under seminatural conditions without females throughout the breeding season. This finding indicates that re-hibernation slows normal rates of sperm ageing and constitutes the first evidence to our knowledge of post-meiotic intra-testicular sperm senescence in a wild vertebrate. We also found that in males kept in seminatural conditions, sperm motility was positively related to the number of matings a male achieved. Thus, our results suggest that post-meiotic intra-testicular sperm senescence does not have a genetically fixed rate and may be modulated by temperature and possibly by mating opportunities.
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Affiliation(s)
- Attila Hettyey
- Department of Integrative Biology and Evolution, Konrad Lorenz Institute of Ethology, University of Veterinary Medicine, Vienna, Austria.
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SHERRATT TN, HASSALL C, LAIRD RA, THOMPSON DJ, CORDERO-RIVERA A. A comparative analysis of senescence in adult damselflies and dragonflies (Odonata). J Evol Biol 2011; 24:810-22. [DOI: 10.1111/j.1420-9101.2010.02222.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Voituron Y, de Fraipont M, Issartel J, Guillaume O, Clobert J. Extreme lifespan of the human fish (Proteus anguinus): a challenge for ageing mechanisms. Biol Lett 2010; 7:105-7. [PMID: 20659920 DOI: 10.1098/rsbl.2010.0539] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Theories of extreme lifespan evolution in vertebrates commonly implicate large size and predator-free environments together with physiological characteristics like low metabolism and high protection against oxidative damages. Here, we show that the 'human fish' (olm, Proteus anguinus), a small cave salamander (weighing 15-20 g), has evolved an extreme life-history strategy with a predicted maximum lifespan of over 100 years, an adult average lifespan of 68.5 years, an age at sexual maturity of 15.6 years and lays, on average, 35 eggs every 12.5 years. Surprisingly, neither its basal metabolism nor antioxidant activities explain why this animal sits as an outlier in the amphibian size/longevity relationship. This species thus raises questions regarding ageing processes and constitutes a promising model for discovering mechanisms preventing senescence in vertebrates.
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Affiliation(s)
- Yann Voituron
- Ecologie des Hydrosystèmes Fluviaux, UMR CNRS 5023, Université Claude Bernard Lyon 1, Université de Lyon, 69622 Villeurbanne cedex, France.
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21
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Haag WR, Rypel AL. Growth and longevity in freshwater mussels: evolutionary and conservation implications. Biol Rev Camb Philos Soc 2010; 86:225-47. [DOI: 10.1111/j.1469-185x.2010.00146.x] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Sherratt TN, Laird RA, Hassall C, Lowe CD, Harvey IF, Watts PC, Cordero-Rivera A, Thompson DJ. Empirical evidence of senescence in adult damselflies (Odonata: Zygoptera). J Anim Ecol 2010; 79:1034-44. [DOI: 10.1111/j.1365-2656.2010.01719.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Laird RA, Sherratt TN. The evolution of senescence in multi-component systems. Biosystems 2010; 99:130-9. [DOI: 10.1016/j.biosystems.2009.10.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2009] [Revised: 08/18/2009] [Accepted: 10/22/2009] [Indexed: 11/28/2022]
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Hayward AD, Wilson AJ, Pilkington JG, Pemberton JM, Kruuk LEB. Ageing in a variable habitat: environmental stress affects senescence in parasite resistance in St Kilda Soay sheep. Proc Biol Sci 2009; 276:3477-85. [PMID: 19586947 PMCID: PMC2817194 DOI: 10.1098/rspb.2009.0906] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Despite widespread empirical evidence for a general deterioration in the majority of traits with advancing age, it is unclear whether the progress of senescence is chronologically determined, or whether factors such as environmental conditions experienced over the lifespan are more important. We explored the relative importance of ‘chronological’ and ‘environmental’ measures of age to changes in parasite resistance across the lifespan of free-living Soay sheep. Our results show that individuals experience an increase in parasite burden, as indicated by gastrointestinal helminth faecal egg count (FEC) with chronological age. However, chronological age fails to fully explain changes in FEC because a measure of environmental age, cumulative environmental stress, predicts an additional increase in FEC once chronological age has been accounted for. Additionally, we show that in females age-specific changes are dependent upon the environmental conditions experienced across individuals' life histories: increases in FEC with age were greatest among individuals that had experienced the highest degree of stress. Our results illustrate that chronological age alone may not always correspond to biological age, particularly in variable environments. In these circumstances, measures of age that capture the cumulative stresses experienced by an individual may be useful for understanding the process of senescence.
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Affiliation(s)
- Adam D Hayward
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, UK.
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LAIRD RA, SHERRATT TN. The evolution of senescence through decelerating selection for system reliability. J Evol Biol 2009; 22:974-82. [DOI: 10.1111/j.1420-9101.2009.01709.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Abstract
Little is known about the effects of inbreeding on reproduction in modern human societies. It appears indeed that biological effects are hidden by socioeconomic factors, which are the major determinants of fertility. It has been established, in particular, that socially induced reproductive compensation tends to homogenize the number of offspring per family in a given population. Besides, in the field of evolutionary biology, a number of empirical and theoretical studies have shown that the effects of inbreeding are condition dependent. In particular, theoretical developments on the evolution of senescence predict that the deleterious effects of inbreeding should increase with age. We rely on these developments to examine the effects of inbreeding on fertility in a cohort of Canadian women born in the late 19th century. The analysis does not allow for the detection of any effect of inbreeding on the overall number of offspring of women. However, results indicate that high levels of close father inbreeding are associated with a reduction of the productivity of parents during the second half of their reproductive period, as compared with the first half. We suggest that inbreeding depression affects reproduction in modern societies through an interaction with age.
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Density dependence, lifespan and the evolutionary dynamics of longevity. Theor Popul Biol 2008; 75:46-55. [PMID: 19027031 DOI: 10.1016/j.tpb.2008.10.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 09/12/2008] [Accepted: 10/21/2008] [Indexed: 12/30/2022]
Abstract
Longevity is a life-history trait that is shaped by natural selection. Evolution will shape mortality trajectories and lifespans, but until now the evolutionary analysis of longevity is based principally on a density-independent (Euler-Lotka) framework. The effects of density dependence on the evolution of lifespan and mortality remain largely unexplored. We investigate the influence of different population demographies on the evolution of longevity, and show how these can be linked to adaptive radiations. We present a range of models to explore the intraspecific and interspecific density effects on longevity and, consequently, diversification. We show how the magnitude, type, and timing of mutation can also affect fitness, invasion and diversification. We argue that fitness of alternative strategies under a range of different demographic structures leads to flat, as opposed to rugged, landscapes and that these flat fitness surfaces are important in the evolution of lifespan and senescence.
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Nikolova-Karakashian M, Karakashian A, Rutkute K. Role of neutral sphingomyelinases in aging and inflammation. Subcell Biochem 2008; 49:469-86. [PMID: 18751923 DOI: 10.1007/978-1-4020-8831-5_18] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Aging is characterized by changes in the organism's immune functions and stress response, which in the elderly leads to increased incidence of complications and mortality following inflammatory stress. Alterations in the neuro-endocrine axes and overall decline in the immune system play an essential role in this process. Overwhelming evidence however suggests that many cellular cytokine signaling pathways are also affected, thus underscoring the idea that both, "cellular" and "systemic" changes contribute to aging. IL-1beta for example, induces more potent cellular responses in hepatocytes isolated from aged animals then in hepatocytes from young rats. This phenomenon is referred to as IL-1b hyperresponsiveness and is linked to abnormal regulation of various acute phase proteins during aging.Evidence has consistently indicated that activation of neutral sphingomyelinase and the resulting accumulation of ceramide mediate cellular responses to LPS, IL-1beta, and TNFalpha in young animals. More recent studies identified the cytokine-inducible neutral sphingomyelinase with nSMase2 (smpd3) that is localized in the plasma membrane and mediates cellular responses to IL-1beta and TNFalpha. Intriguingly, constitutive up-regulation of nSMase2 occurs in aging and it underlies the hepatic IL-1b hyperresponsiveness. The increased activity of nSMases2 in aging is caused by a substantial decline in hepatic GSH content linking thereby oxidative stress to the onset of pro-inflammatory state in liver. nSMase2 apparently follows a pattern of regulation consisting with "developmental-aging" continuum, since in animal models of delayed aging, like calorie-restricted animals, the aging-associated changes in NSMase activity and function are reversed.
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31
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Ricklefs RE, Cadena CD. Heritability of Longevity in Captive Populations of Nondomesticated Mammals and Birds. J Gerontol A Biol Sci Med Sci 2008; 63:435-46. [DOI: 10.1093/gerona/63.5.435] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Pizzari T, Dean R, Pacey A, Moore H, Bonsall MB. The evolutionary ecology of pre- and post-meiotic sperm senescence. Trends Ecol Evol 2008; 23:131-40. [PMID: 18280006 DOI: 10.1016/j.tree.2007.12.003] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Revised: 12/13/2007] [Accepted: 12/13/2007] [Indexed: 02/07/2023]
Affiliation(s)
- Tom Pizzari
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK.
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Bourke AF. Kin Selection and the Evolutionary Theory of Aging. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2007. [DOI: 10.1146/annurev.ecolsys.38.091206.095528] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Andrew F.G. Bourke
- School of Biological Sciences, University of East Anglia, Norwich, Norfolk NR4 7TJ, United Kingdom;
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Mangel M, Kindsvater HK, Bonsall MB. Evolutionary analysis of life span, competition, and adaptive radiation, motivated by the Pacific rockfishes (Sebastes). Evolution 2007; 61:1208-24. [PMID: 17492972 DOI: 10.1111/j.1558-5646.2007.00094.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The Pacific rockfishes (Sebastes spp) are remarkable for both their diversity (on the order of 100 species) and range of maximum life span ( approximately 10 years for Calico rockfish to approximately 200 years for Rougheye rockfish). We describe the natural history and patterns of diversity and life span in these species and then use independent contrasts to explore correlates of these. When phylogenetic history is taken into account, maximum life span is explained by age at maturity, size at maturity, and the interaction of these two. We introduce a life-history model that allows insight into the origin of these correlations. We then describe a variety of mechanisms that may increase lifepans and diversity. These include fluctuating environments (in which organisms basically have to "wait out" bad periods to reproduce successfully), diversity, and longevity inspired by interspecific competition and physiological complexity in growth and accumulation of cellular damage. All of the results point toward the importance of flat or "indifferent" fitness surfaces as a key element in the evolution of diversity. We conclude that further development of the theory of flat or indifferent fitness surfaces as applied to diversity and life span is clearly warranted.
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Affiliation(s)
- Marc Mangel
- Center for Stock Assessment Research and Department of Applied Mathematics and Statistics, University of California, Santa Cruz, California 95064, USA.
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Torigian DA, Alavi A. The Evolving Role of Structural and Functional Imaging in Assessment of Age-Related Changes in the Body. Semin Nucl Med 2007; 37:64-8. [PMID: 17289455 DOI: 10.1053/j.semnuclmed.2006.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Aging is an extremely complex, multifactorial, and inevitable process that varies in rate from person to person and that is not fully understood at its most basic levels. Despite this complexity, knowledge of age-related changes and normal variation in organ structure and function is essential to differentiate them from alterations that are associated with pathology. Combined structural and functional imaging, which increasingly is used to assess a multitude of disorders, including cancer, cardiovascular disease, and central nervous system abnormalities, can be applied to study changes in structure and function related to aging. This article reviews the major theories of biological aging and presents our approach and rationale to study age-related changes through quantitative tomographic radiological and scintigraphic approaches. In the series of articles that follow, we have made an attempt to determine age-related changes in volume, attenuation, and function as measured by computed tomography, magnetic resonance imaging, and position emission tomography in the following organs and systems: central nervous system, head and neck, heart and major arteries, lungs, abdominal and pelvic parenchymal organs, gastrointestinal tract, genitourinary tract, breast, bone and bone marrow, joints, and skin. The population examined includes a large number of subjects in all decades of life. We have also made an effort to introduce some new concepts such as partial volume correction and measurements of global metabolic activity of the organs examined, and emphasize the importance of quantitative techniques in such applications. It is our hope that this new initiative will further enhance the role of novel imaging techniques in the management of patients with cancer and other disorders.
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Affiliation(s)
- Drew A Torigian
- Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-4283, USA.
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