1
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Cutter AD. Sexual conflict, heterochrony and tissue specificity as evolutionary problems of adaptive plasticity in development. Proc Biol Sci 2023; 290:20231854. [PMID: 37817601 PMCID: PMC10565415 DOI: 10.1098/rspb.2023.1854] [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: 08/16/2023] [Accepted: 09/15/2023] [Indexed: 10/12/2023] Open
Abstract
Differential gene expression represents a fundamental cause and manifestation of phenotypic plasticity. Adaptive phenotypic plasticity in gene expression as a trait evolves when alleles that mediate gene regulation serve to increase organismal fitness by improving the alignment of variation in gene expression with variation in circumstances. Among the diverse circumstances that a gene encounters are distinct cell types, developmental stages and sexes, as well as an organism's extrinsic ecological environments. Consequently, adaptive phenotypic plasticity provides a common framework to consider diverse evolutionary problems by considering the shared implications of alleles that produce context-dependent gene expression. From this perspective, adaptive plasticity represents an evolutionary resolution to conflicts of interest that arise from any negatively pleiotropic effects of expression of a gene across ontogeny, among tissues, between the sexes, or across extrinsic environments. This view highlights shared properties within the general relation of fitness, trait expression and context that may nonetheless differ substantively in the grain of selection within and among generations to influence the likelihood of adaptive plasticity as an evolutionary response. Research programmes that historically have focused on these separate issues may use the insights from one another by recognizing their shared dependence on context-dependent gene regulatory evolution.
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Affiliation(s)
- Asher D. Cutter
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada M5S 3B2
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2
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Santos J, Matos M, Flatt T, Chelo IM. Microbes are potential key players in the evolution of life histories and aging in Caenorhabditis elegans. Ecol Evol 2023; 13:e10537. [PMID: 37753311 PMCID: PMC10518755 DOI: 10.1002/ece3.10537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 08/07/2023] [Accepted: 09/01/2023] [Indexed: 09/28/2023] Open
Abstract
Microbes can have profound effects on host fitness and health and the appearance of late-onset diseases. Host-microbe interactions thus represent a major environmental context for healthy aging of the host and might also mediate trade-offs between life-history traits in the evolution of host senescence. Here, we have used the nematode Caenorhabditis elegans to study how host-microbe interactions may modulate the evolution of life histories and aging. We first characterized the effects of two non-pathogenic and one pathogenic Escherichia coli strains, together with the pathogenic Serratia marcescens DB11 strain, on population growth rates and survival of C. elegans from five different genetic backgrounds. We then focused on an outbred C. elegans population, to understand if microbe-specific effects on the reproductive schedule and in traits such as developmental rate and survival were also expressed in the presence of males and standing genetic variation, which could be relevant for the evolution of C. elegans and other nematode species in nature. Our results show that host-microbe interactions have a substantial host-genotype-dependent impact on the reproductive aging and survival of the nematode host. Although both pathogenic bacteria reduced host survival in comparison with benign strains, they differed in how they affected other host traits. Host fertility and population growth rate were affected by S. marcescens DB11 only during early adulthood, whereas this occurred at later ages with the pathogenic E. coli IAI1. In both cases, these effects were largely dependent on the host genotypes. Given such microbe-specific genotypic differences in host life history, we predict that the evolution of reproductive schedules and senescence might be critically contingent on host-microbe interactions in nature.
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Affiliation(s)
- Josiane Santos
- cE3c – Centre for Ecology, Evolution and Environmental Changes & CHANGE – Global Change and Sustainability InstituteLisboaPortugal
- Departamento de Biologia Animal, Faculdade de CiênciasUniversidade de LisboaLisboaPortugal
| | - Margarida Matos
- cE3c – Centre for Ecology, Evolution and Environmental Changes & CHANGE – Global Change and Sustainability InstituteLisboaPortugal
- Departamento de Biologia Animal, Faculdade de CiênciasUniversidade de LisboaLisboaPortugal
| | - Thomas Flatt
- Department of BiologyUniversity of FribourgFribourgSwitzerland
| | - Ivo M. Chelo
- cE3c – Centre for Ecology, Evolution and Environmental Changes & CHANGE – Global Change and Sustainability InstituteLisboaPortugal
- Departamento de Biologia Animal, Faculdade de CiênciasUniversidade de LisboaLisboaPortugal
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3
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Vrtílek M, Žák J, Reichard M. Evidence for reproductive senescence across ray-finned fishes: A review. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.982915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The origin, incidence, and consequences of reproductive senescence vary greatly across the tree of life. In vertebrates, research on reproductive senescence has been mainly focused on mammals and birds, demonstrating that its variation is largely linked to critical life history traits, such as growth patterns, juvenile, and adult mortality, and reproductive strategy. Fishes represent half of the vertebrate taxonomic diversity and display remarkable variation in life history. Based on a thorough literature review, we summarize current evidence on reproductive senescence in ray-finned fishes (Actinopterygii). While survival and physiological senescence are acknowledged in fish, their potential age-related reproductive decline has often been disregarded due to the prevalence of indeterminate growth. We demonstrate that age-related reproductive decline is reported across fish phylogeny, environments, and traits. An important point of our review is that the incidence of reproductive senescence in a species depends on both the number of studies for that species and the coverage of its maximum lifespan by the study. Reproductive senescence was documented for one-third of the studied fish species, with females suffering an age-related decline in reproductive traits less often than males or both parents combined. Neither parental care nor migratory strategy corresponded with the occurrence of reproductive senescence in fish. The traits that were affected by reproductive senescence most often were sex-specific, with pre-mating and mating categories of traits declining in females and sperm quality and quantity in males. We also demonstrate that reproductive senescence can be buffered by indeterminate growth. We provide rich evidence of reproductive senescence across ray-finned fishes, but we highlight the need for better data on age-related reproduction in fishes.
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4
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Omotoso O, Gladyshev VN, Zhou X. Lifespan Extension in Long-Lived Vertebrates Rooted in Ecological Adaptation. Front Cell Dev Biol 2021; 9:704966. [PMID: 34733838 PMCID: PMC8558438 DOI: 10.3389/fcell.2021.704966] [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: 05/04/2021] [Accepted: 09/02/2021] [Indexed: 01/21/2023] Open
Abstract
Contemporary studies on aging and longevity have largely overlooked the role that adaptation plays in lifespan variation across species. Emerging evidence indicates that the genetic signals of extended lifespan may be maintained by natural selection, suggesting that longevity could be a product of organismal adaptation. The mechanisms of adaptation in long-lived animals are believed to account for the modification of physiological function. Here, we first review recent progress in comparative biology of long-lived animals, together with the emergence of adaptive genetic factors that control longevity and disease resistance. We then propose that hitchhiking of adaptive genetic changes is the basis for lifespan changes and suggest ways to test this evolutionary model. As individual adaptive or adaptation-linked mutations/substitutions generate specific forms of longevity effects, the cumulative beneficial effect is largely nonrandom and is indirectly favored by natural selection. We consider this concept in light of other proposed theories of aging and integrate these disparate ideas into an adaptive evolutionary model, highlighting strategies in decoding genetic factors of lifespan control.
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Affiliation(s)
- Olatunde Omotoso
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Vadim N Gladyshev
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, United States
| | - Xuming Zhou
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, China
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5
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Abstract
Aging has provided fruitful challenges for evolutionary theory, and evolutionary theory has deepened our understanding of aging. A great deal of genetic and molecular data now exists concerning mortality regulation and there is a growing body of knowledge concerning the life histories of diverse species. Assimilating all relevant data into a framework for the evolution of aging promises to significantly advance the field. We propose extensions of some key concepts to provide greater precision when applying these concepts to age-structured contexts. Secondary or byproduct effects of mutations are proposed as an important factor affecting survival patterns, including effects that may operate in small populations subject to genetic drift, widening the possibilities for mutation accumulation and pleiotropy. Molecular and genetic studies have indicated a diverse array of mechanisms that can modify aging and mortality rates, while transcriptome data indicate a high level of tissue and species specificity for genes affected by aging. The diversity of mechanisms and gene effects that can contribute to the pattern of aging in different organisms may mirror the complex evolutionary processes behind aging.
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Affiliation(s)
- Stewart Frankel
- Biology Department, University of Hartford, West Hartford, CT, United States
| | - Blanka Rogina
- Genetics and Genome Sciences, Institute for Systems Genomics, School of Medicine, University of Connecticut Health Center, Farmington, CT, United States
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6
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Oosthuizen WC, Péron G, Pradel R, Bester MN, de Bruyn PJN. Positive early-late life-history trait correlations in elephant seals. Ecology 2021; 102:e03288. [PMID: 33481267 DOI: 10.1002/ecy.3288] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 11/12/2020] [Indexed: 01/24/2023]
Abstract
Correlations between early- and late-life performance are a major prediction of life-history theory. Negative early-late correlations can emerge because biological processes are optimized for early but not late life (e.g., rapid development may accelerate the onset of senescence; "developmental theory of aging") or because allocation to early-life performance comes at a cost in terms of late-life performance (as in the disposable soma theory). But variation in genetic and environmental challenges that each individual has to cope with during early life may also lead to positive early-late life-history trait correlations (the "fixed heterogeneity" or "individual quality" hypothesis). We analyzed individual life-history trajectories of 7,420 known-age female southern elephant seals (Mirounga leonina) monitored over 36 yr to determine how actuarial senescence (a proxy for late-life performance) correlate with age at first reproduction (a proxy for early-life performance). As some breeding events may not be detected in this field study, we used a custom "multievent" hierarchical model to estimate the age at first reproduction and correlate it to other life-history traits. The probability of first reproduction was 0.34 at age 3, with most females breeding for the first time at age 4, and comparatively few at older ages. Females with an early age of first reproduction outperformed delayed breeders in all aspects we considered (survival, rate of senescence, net reproductive output) but one: early breeders appeared to have an onset of actuarial senescence 1 yr earlier compared to late breeders. Genetics and environmental conditions during early life likely explain the positive correlation between early- and late-life performance. Our results provide the first evidence of actuarial senescence in female southern elephant seals.
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Affiliation(s)
- W Chris Oosthuizen
- Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Private Bag X20, Hatfield, 0028, South Africa.,Marine Apex Predator Research Unit, Institute for Coastal and Marine Research and Department of Zoology, Nelson Mandela University, Port Elizabeth, 6031, South Africa
| | - Guillaume Péron
- CNRS, Laboratoire de Biométrie et Biologie Évolutive, UMR5558, Université de Lyon, Université Lyon 1, Villeurbanne, France
| | - Roger Pradel
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Univ Paul Valéry Montpellier 3, Montpellier, France
| | - Marthán N Bester
- Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Private Bag X20, Hatfield, 0028, South Africa
| | - P J Nico de Bruyn
- Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Private Bag X20, Hatfield, 0028, South Africa
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7
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Žák J, Reichard M. Reproductive senescence in a short-lived fish. J Anim Ecol 2020; 90:492-502. [PMID: 33159690 DOI: 10.1111/1365-2656.13382] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 11/02/2020] [Indexed: 12/13/2022]
Abstract
Reproductive senescence is an age-associated decline in reproductive performance, which often arises as a trade-off between current and future reproduction. Given that mortality is inevitable, increased allocation into current reproduction is favoured despite costs paid later in life. This assumption is violated in organisms with post-maturity growth whose reproductive output increases long after maturity. While reproductive senescence is frequently studied in animals with determinate growth at maturity, such as insects or mammals, we have very limited understanding of reproductive senescence in organisms with an extensive post-maturity growth period. The fact that many post-maturity growers experience strong adult mortality leads to conflicting expectations for reproductive senescence. The aim of this study was to investigate how co-occurrence of rapid life history and post-maturity growth mould reproductive senescence in a short-lived killifish, Nothobranchius furzeri, using longitudinal data on laboratory and wild-type populations. We followed the individual fecundity, fertility and fertilization of 132 singly housed fish from the perspectives of chronological and biological age. At the onset of senescence, the sex-specific contribution to decrease in fertilization capacity was investigated. Allocation trade-offs were estimated through the association between reproductive parameters and life span, and between early-life and late-life fecundity. We demonstrate that female fecundity increased steadily after maturity and reproductive senescence occurred long after the growth asymptote. The prime age for fecundity coincided with 50% female survival and consequent decline in fecundity implies an association with somatic deterioration. Reproductive senescence in fertilization rate was stronger in females than in males. Females with high early fecundity experienced a long life span and high late-life fecundity, discounting the role of allocation trade-offs in reproductive senescence. The present study reports a clear case of reproductive senescence in a fish with a long post-maturation growth period, unusually rapid development and short life span. The onset of reproductive senescence was postponed compared to animals that cease growing at sexual maturity. Fish and other animals with post-maturity growth have long been considered insusceptible to ageing but this conclusion may be related to the previous lack of longitudinal data rather than to the absence of reproductive senescence in such organisms.
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Affiliation(s)
- Jakub Žák
- Institute of Vertebrate Biology of the Czech Academy of Sciences, Brno, Czech Republic.,Department of Zoology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Martin Reichard
- Institute of Vertebrate Biology of the Czech Academy of Sciences, Brno, Czech Republic.,Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic
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8
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Brengdahl MI, Kimber CM, Elias P, Thompson J, Friberg U. Deleterious mutations show increasing negative effects with age in Drosophila melanogaster. BMC Biol 2020; 18:128. [PMID: 32993647 PMCID: PMC7526172 DOI: 10.1186/s12915-020-00858-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 08/28/2020] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND In order for aging to evolve in response to a declining strength of selection with age, a genetic architecture that allows for mutations with age-specific effects on organismal performance is required. Our understanding of how selective effects of individual mutations are distributed across ages is however poor. Established evolutionary theories assume that mutations causing aging have negative late-life effects, coupled to either positive or neutral effects early in life. New theory now suggests evolution of aging may also result from deleterious mutations with increasing negative effects with age, a possibility that has not yet been empirically explored. RESULTS To directly test how the effects of deleterious mutations are distributed across ages, we separately measure age-specific effects on fecundity for each of 20 mutations in Drosophila melanogaster. We find that deleterious mutations in general have a negative effect that increases with age and that the rate of increase depends on how deleterious a mutation is early in life. CONCLUSIONS Our findings suggest that aging does not exclusively depend on genetic variants assumed by the established evolutionary theories of aging. Instead, aging can result from deleterious mutations with negative effects that amplify with age. If increasing negative effect with age is a general property of deleterious mutations, the proportion of mutations with the capacity to contribute towards aging may be considerably larger than previously believed.
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Affiliation(s)
| | | | - Phoebe Elias
- IFM Biology, Linköping University, Linköping, Sweden
| | | | - Urban Friberg
- IFM Biology, Linköping University, Linköping, Sweden.
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9
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Žák J, Reichard M. Fluctuating temperatures extend median lifespan, improve reproduction and reduce growth in turquoise killifish. Exp Gerontol 2020; 140:111073. [PMID: 32858146 DOI: 10.1016/j.exger.2020.111073] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 08/12/2020] [Accepted: 08/22/2020] [Indexed: 12/12/2022]
Abstract
In natural populations, individuals experience daily fluctuations in environmental conditions that synchronise endogenous biorhythms. Artificial alterations of environmental fluctuations can have negative consequences for life history traits, including lifespan. In laboratory studies of aging, the role of fluctuating temperature is usually overlooked and we know little of how thermal fluctuation modulates senescence in vertebrates. In this longitudinal study we followed individually-housed turquoise killifish, Nothobranchius furzeri, from two thermal regimes; ecologically relevant diel fluctuations (20 °C - 35 °C) and stable temperature (27.5 °C), and compared their survival, growth and reproduction. Fish experiencing fluctuating temperatures had a longer median lifespan but reached smaller asymptotic body size. Within-treatment variation indicated that extended lifespan in fluctuating temperatures was not causally linked to decreased growth rate or smaller body size, but occurred solely due to the effect of thermal fluctuations. Male body size was positively associated with lifespan in stable temperatures but this relationship was disrupted in fluctuating thermal regimes. Females exposed to fluctuating temperatures effectively compensated egg production for their smaller size. Thus, there was no difference in absolute fecundity between thermal regimes and body-size corrected fecundity was higher in females in fluctuating temperatures. Overall, despite a brief exposure to sub-optimal thermal conditions during fluctuations, fluctuating temperature had a positive effect on survival and reproduction. These results suggest that the expression of life history traits and their associations under stable temperatures are a poor representation of the relationships obtained from ecologically relevant thermal fluctuations.
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Affiliation(s)
- Jakub Žák
- Institute of Vertebrate Biology of the Czech Academy of Sciences, Květná 8, 603 65 Brno, Czechia; Department of Zoology, Faculty of Science, Charles University, Prague, Viničná 7, 128 00, Czechia
| | - Martin Reichard
- Institute of Vertebrate Biology of the Czech Academy of Sciences, Květná 8, 603 65 Brno, Czechia; Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czechia.
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10
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Zhang B, Gladyshev VN. How can aging be reversed? Exploring rejuvenation from a damage-based perspective. ADVANCED GENETICS (HOBOKEN, N.J.) 2020; 1:e10025. [PMID: 36619246 PMCID: PMC9744548 DOI: 10.1002/ggn2.10025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 03/13/2020] [Accepted: 03/17/2020] [Indexed: 01/11/2023]
Abstract
Advanced age is associated with accumulation of damage and other deleterious changes and a consequential systemic decline of function. This decline affects all organs and systems in an organism, leading to their inadaptability to the environment, and therefore is thought to be inevitable for humans and most animal species. However, in vitro and in vivo application of reprogramming strategies, which convert somatic cells to induced pluripotent stem cells, has demonstrated that the aged cells can be rejuvenated. Moreover, the data and theoretical considerations suggest that reversing the biological age of somatic cells (from old to young) and de-differentiating somatic cells into stem cells represent two distinct processes that take place during rejuvenation, and thus they may be differently targeted. We advance a stemness-function model to explain these data and discuss a possibility of rejuvenation from the perspective of damage accumulation. In turn, this suggests approaches to achieve rejuvenation of cells in vitro and in vivo.
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Affiliation(s)
- Bohan Zhang
- Division of Genetics, Department of Medicine, Brigham and Women's HospitalHarvard Medical SchoolBostonMassachusettsUSA
| | - Vadim N. Gladyshev
- Division of Genetics, Department of Medicine, Brigham and Women's HospitalHarvard Medical SchoolBostonMassachusettsUSA
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11
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Muntané G, Farré X, Bosch E, Martorell L, Navarro A, Vilella E. The shared genetic architecture of schizophrenia, bipolar disorder and lifespan. Hum Genet 2020; 140:441-455. [PMID: 32772156 DOI: 10.1007/s00439-020-02213-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 07/27/2020] [Indexed: 12/11/2022]
Abstract
Psychiatric disorders such as Schizophrenia (SCZ) and Bipolar Disorder (BD) represent an evolutionary paradox, as they exhibit strong negative effects on fitness, such as decreased fecundity and early mortality, yet they persist at a worldwide prevalence of approximately 1%. Molecular mechanisms affecting lifespan, which may be widely common among complex diseases with fitness effects, can be studied by the integrated analysis of data from genome-wide association studies (GWAS) of human longevity together with any disease of interest. Here, we report the first of such studies, focusing on the genetic overlap-pleiotropy-between two psychiatric disorders with shortened lifespan, SCZ and BD, and human parental lifespan (PLS) as a surrogate of life expectancy. Our results are twofold: first, we demonstrate extensive polygenic overlap between SCZ and PLS and to a lesser extent between BD and PLS. Second, we identified novel loci shared between PLS and SCZ (n = 39), and BD (n = 8). Whereas most of the identified SCZ (66%) and BD (62%) pleiotropic risk alleles were associated with reduced lifespan, we also detected some antagonistic protective alleles associated to shorter lifespans. In fact, top-associated SNPs with SCZ seems to explain longevity variance explained (LVE) better than many other life-threatening diseases, including Type 2 diabetes and most cancers, probably due to a high overlap with smoking-related pathways. Overall, our study provides evidence of a genetic burden driven through premature mortality among people with SCZ, which can have profound implications for understanding, and potentially treating, the mortality gap associated with this psychiatric disorder.
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Affiliation(s)
- Gerard Muntané
- Biomedical Network Research Centre on Mental Health (CIBERSAM), Hospital Universitari Institut Pere Mata, IISPV Universitat Rovira i Virgili, Reus, Spain. .,Departament de Ciències Experimentals i de la Salut, Institut de Biologia Evolutiva (UPF-CSIC), Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona, Spain.
| | - Xavier Farré
- Departament de Ciències Experimentals i de la Salut, Institut de Biologia Evolutiva (UPF-CSIC), Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona, Spain
| | - Elena Bosch
- Departament de Ciències Experimentals i de la Salut, Institut de Biologia Evolutiva (UPF-CSIC), Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona, Spain
| | - Lourdes Martorell
- Biomedical Network Research Centre on Mental Health (CIBERSAM), Hospital Universitari Institut Pere Mata, IISPV Universitat Rovira i Virgili, Reus, Spain
| | - Arcadi Navarro
- Departament de Ciències Experimentals i de la Salut, Institut de Biologia Evolutiva (UPF-CSIC), Universitat Pompeu Fabra, Parc de Recerca Biomèdica de Barcelona, Barcelona, Spain.,Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats, ICREA, Barcelona, Spain.,Barcelonaβeta Brain Research Center, Fundació Pasqual Maragall, Barcelona, Spain
| | - Elisabet Vilella
- Biomedical Network Research Centre on Mental Health (CIBERSAM), Hospital Universitari Institut Pere Mata, IISPV Universitat Rovira i Virgili, Reus, Spain
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12
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Sultanova Z, García-Roa R, Carazo P. Condition-dependent mortality exacerbates male (but not female) reproductive senescence and the potential for sexual conflict. J Evol Biol 2020; 33:1086-1096. [PMID: 32335965 DOI: 10.1111/jeb.13636] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 04/02/2020] [Indexed: 01/10/2023]
Abstract
Disentangling the relationship between age and reproduction is central to understand life-history evolution, and recent evidence shows that considering condition-dependent mortality is a crucial piece of this puzzle. For example, nonrandom mortality of 'low-condition' individuals can lead to an increase in average lifespan. However, selective disappearance of such low-condition individuals may also affect reproductive senescence at the population level due to trade-offs between physiological functions related to survival/lifespan and the maintenance of reproductive functions. Here, we address the idea that condition-dependent extrinsic mortality (i.e. simulated predation) may increase the age-related decline in male reproductive success and with it the potential for sexual conflict, by comparing reproductive ageing in Drosophila melanogaster male/female cohorts exposed (or not) to condition-dependent simulated predation across time. Although female reproductive senescence was not affected by predation, male reproductive senescence was considerably higher under predation, due mainly to an accelerated decline in offspring viability of 'surviving' males with age. This sex-specific effect suggests that condition-dependent extrinsic mortality can exacerbate survival-reproduction trade-offs in males, which are typically under stronger condition-dependent selection than females. Interestingly, condition-dependent extrinsic mortality did not affect mating success, hinting that accelerated reproductive senescence is due to a decrease in male post-copulatory fitness components. Our results support the recent proposal that male ageing can be an important source of sexual conflict, further suggesting this effect could be exacerbated under more natural conditions.
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Affiliation(s)
- Zahida Sultanova
- Ecology, Ethology and Evolution Group, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, Valencia, Spain
| | - Roberto García-Roa
- Ecology, Ethology and Evolution Group, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, Valencia, Spain
| | - Pau Carazo
- Ecology, Ethology and Evolution Group, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, Valencia, Spain
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13
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Vineis P, Avendano-Pabon M, Barros H, Bartley M, Carmeli C, Carra L, Chadeau-Hyam M, Costa G, Delpierre C, D'Errico A, Fraga S, Giles G, Goldberg M, Kelly-Irving M, Kivimaki M, Lepage B, Lang T, Layte R, MacGuire F, Mackenbach JP, Marmot M, McCrory C, Milne RL, Muennig P, Nusselder W, Petrovic D, Polidoro S, Ricceri F, Robinson O, Stringhini S, Zins M. Special Report: The Biology of Inequalities in Health: The Lifepath Consortium. Front Public Health 2020; 8:118. [PMID: 32478023 PMCID: PMC7235337 DOI: 10.3389/fpubh.2020.00118] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 03/24/2020] [Indexed: 12/16/2022] Open
Abstract
Funded by the European Commission Horizon 2020 programme, the Lifepath research consortium aimed to investigate the effects of socioeconomic inequalities on the biology of healthy aging. The main research questions included the impact of inequalities on health, the role of behavioral and other risk factors, the underlying biological mechanisms, the efficacy of selected policies, and the general implications of our findings for theories and policies. The project adopted a life-course and comparative approach, considering lifetime effects from childhood and adulthood, and pooled data on up to 1.7 million participants of longitudinal cohort studies from Europe, USA, and Australia. These data showed that socioeconomic circumstances predicted mortality and functional decline as strongly as established risk factors currently targeted by global prevention programmes. Analyses also looked at socioeconomically patterned biological markers, allostatic load, and DNA methylation using richly phenotyped cohorts, unraveling their association with aging processes across the life-course. Lifepath studies suggest that socioeconomic circumstances are embedded in our biology from the outset—i.e., disadvantage influences biological systems from molecules to organs. Our findings have important implications for policy, suggesting that (a) intervening on unfavorable socioeconomic conditions is complementary and as important as targeting well-known risk factors, such as tobacco and alcohol consumption, low fruit and vegetable intake, obesity and a sedentary lifestyle, and that (b) effects of preventive interventions in early life integrate interventions in adulthood. The report has an executive summary that refers to the different sections of the main paper.
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Affiliation(s)
- Paolo Vineis
- Department of Epidemiology and Biostatistics, Imperial College London, London, United Kingdom
| | - Mauricio Avendano-Pabon
- Department of Social Sciences, Health and Medicine, King's College London, London, United Kingdom
| | - Henrique Barros
- EPIUnit - Institute of Public Health University of Porto, Porto, Portugal
| | - Mel Bartley
- Department of Epidemiology & Public Health, University College London, London, United Kingdom
| | - Cristian Carmeli
- Center for Primary Care and Public Health (UNISANTE), University of Lausanne, Lausanne, Switzerland
| | | | - Marc Chadeau-Hyam
- Department of Epidemiology and Biostatistics, Imperial College London, London, United Kingdom
| | - Giuseppe Costa
- Department of Clinical Science & Biology, Turin University Medical School, Turin, Italy
| | - Cyrille Delpierre
- UMR LEASP, Université de Toulouse III, UPS, Inserm, Toulouse, France
| | | | - Silvia Fraga
- EPIUnit - Institute of Public Health University of Porto, Porto, Portugal
| | - Graham Giles
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, VIC, Australia.,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC, Australia.,Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Melbourne, VIC, Australia
| | - Marcel Goldberg
- UMS 011 Inserm - UVSQ ≪ Cohortes épidémiologiques en population ≫, Villejuif, France
| | | | - Mika Kivimaki
- Department of Epidemiology and Public Health, University College London, London, United Kingdom
| | - Benoit Lepage
- UMR LEASP, Université de Toulouse III, UPS, Inserm, Toulouse, France
| | - Thierry Lang
- UMR LEASP, Université de Toulouse III, UPS, Inserm, Toulouse, France
| | - Richard Layte
- Department of Sociology, School of Social Sciences and Philosophy, Trinity College Dublin, Dublin, Ireland
| | - Frances MacGuire
- Department of Epidemiology and Public Health, University College London, London, United Kingdom
| | - Johan P Mackenbach
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Michael Marmot
- Department of Epidemiology and Public Health, University College London, London, United Kingdom
| | - Cathal McCrory
- Department of Medical Gerontology, Trinity College Dublin, Dublin, Ireland
| | - Roger L Milne
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, VIC, Australia.,Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC, Australia.,Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Melbourne, VIC, Australia
| | - Peter Muennig
- Mailman School of Public Health, Columbia University, New York, NY, United States
| | - Wilma Nusselder
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Dusan Petrovic
- Center for Primary Care and Public Health (UNISANTE), University of Lausanne, Lausanne, Switzerland
| | - Silvia Polidoro
- Molecular Epidemiology and Exposomics Unit, Italian Institute for Genomic Medicine, Turin, Italy
| | - Fulvio Ricceri
- Department of Clinical Science & Biology, Turin University Medical School, Turin, Italy.,Department of Epidemiology, ASL TO3, Turin, Italy
| | - Oliver Robinson
- Department of Epidemiology and Biostatistics, Imperial College London, London, United Kingdom
| | - Silvia Stringhini
- Unit of Population Epidemiology, Division of Primary Care, Geneva University Hospitals, Geneva, Switzerland
| | - Marie Zins
- UMS 011 Inserm - UVSQ ≪ Cohortes épidémiologiques en population ≫, Villejuif, France
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14
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Iacono D, Feltis GC. Impact of Apolipoprotein E gene polymorphism during normal and pathological conditions of the brain across the lifespan. Aging (Albany NY) 2020; 11:787-816. [PMID: 30677746 PMCID: PMC6366964 DOI: 10.18632/aging.101757] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 01/05/2019] [Indexed: 12/12/2022]
Abstract
The central nervous system (CNS) is the cellular substrate for the integration of complex, dynamic, constant, and simultaneous interactions among endogenous and exogenous stimuli across the entire human lifespan. Numerous studies on aging-related brain diseases show that some genes identified as risk factors for some of the most common neurodegenerative diseases - such as the allele 4 of APOE gene (APOE4) for Alzheimer's disease (AD) - have a much earlier neuro-anatomical and neuro-physiological impact. The impact of APOE polymorphism appears in fact to start as early as youth and early-adult life. Intriguingly, though, those same genes associated with aging-related brain diseases seem to influence different aspects of the brain functioning much earlier actually, that is, even from the neonatal periods and earlier. The APOE4, an allele classically associated with later-life neurodegenerative disorders as AD, seems in fact to exert a series of very early effects on phenomena of neuroplasticity and synaptogenesis that begin from the earliest periods of life such as the fetal ones.We reviewed some of the findings supporting the hypothesis that APOE polymorphism is an early modifier of various neurobiological aspects across the entire human lifespan - from the in-utero to the centenarian life - during both normal and pathological conditions of the brain.
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Affiliation(s)
- Diego Iacono
- Neuropathology Research, Biomedical Research Institute of New Jersey (BRInj), Cedar Knolls, NJ 07927, USA.,MidAtlantic Neonatology Associates (MANA), Morristown, NJ 07960, USA.,Atlantic Neuroscience Institute, Atlantic Health System (AHS), Overlook Medical Center, Summit, NJ 07901, USA
| | - Gloria C Feltis
- Neuropathology Research, Biomedical Research Institute of New Jersey (BRInj), Cedar Knolls, NJ 07927, USA
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15
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Vineis P, Avendano-Pabon M, Barros H, Bartley M, Carmeli C, Carra L, Chadeau-Hyam M, Costa G, Delpierre C, D'Errico A, Fraga S, Giles G, Goldberg M, Kelly-Irving M, Kivimaki M, Lepage B, Lang T, Layte R, MacGuire F, Mackenbach JP, Marmot M, McCrory C, Milne RL, Muennig P, Nusselder W, Petrovic D, Polidoro S, Ricceri F, Robinson O, Stringhini S, Zins M. Special Report: The Biology of Inequalities in Health: The Lifepath Consortium. Front Public Health 2020. [PMID: 32478023 DOI: 10.3389/fpubh.2020.00118/full] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/22/2023] Open
Abstract
Funded by the European Commission Horizon 2020 programme, the Lifepath research consortium aimed to investigate the effects of socioeconomic inequalities on the biology of healthy aging. The main research questions included the impact of inequalities on health, the role of behavioral and other risk factors, the underlying biological mechanisms, the efficacy of selected policies, and the general implications of our findings for theories and policies. The project adopted a life-course and comparative approach, considering lifetime effects from childhood and adulthood, and pooled data on up to 1.7 million participants of longitudinal cohort studies from Europe, USA, and Australia. These data showed that socioeconomic circumstances predicted mortality and functional decline as strongly as established risk factors currently targeted by global prevention programmes. Analyses also looked at socioeconomically patterned biological markers, allostatic load, and DNA methylation using richly phenotyped cohorts, unraveling their association with aging processes across the life-course. Lifepath studies suggest that socioeconomic circumstances are embedded in our biology from the outset-i.e., disadvantage influences biological systems from molecules to organs. Our findings have important implications for policy, suggesting that (a) intervening on unfavorable socioeconomic conditions is complementary and as important as targeting well-known risk factors, such as tobacco and alcohol consumption, low fruit and vegetable intake, obesity and a sedentary lifestyle, and that (b) effects of preventive interventions in early life integrate interventions in adulthood. The report has an executive summary that refers to the different sections of the main paper.
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Affiliation(s)
- Paolo Vineis
- Department of Epidemiology and Biostatistics, Imperial College London, London, United Kingdom
| | - Mauricio Avendano-Pabon
- Department of Social Sciences, Health and Medicine, King's College London, London, United Kingdom
| | - Henrique Barros
- EPIUnit - Institute of Public Health University of Porto, Porto, Portugal
| | - Mel Bartley
- Department of Epidemiology & Public Health, University College London, London, United Kingdom
| | - Cristian Carmeli
- Center for Primary Care and Public Health (UNISANTE), University of Lausanne, Lausanne, Switzerland
| | | | - Marc Chadeau-Hyam
- Department of Epidemiology and Biostatistics, Imperial College London, London, United Kingdom
| | - Giuseppe Costa
- Department of Clinical Science & Biology, Turin University Medical School, Turin, Italy
| | - Cyrille Delpierre
- UMR LEASP, Université de Toulouse III, UPS, Inserm, Toulouse, France
| | | | - Silvia Fraga
- EPIUnit - Institute of Public Health University of Porto, Porto, Portugal
| | - Graham Giles
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, VIC, Australia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC, Australia
- Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Melbourne, VIC, Australia
| | - Marcel Goldberg
- UMS 011 Inserm - UVSQ ≪ Cohortes épidémiologiques en population ≫, Villejuif, France
| | | | - Mika Kivimaki
- Department of Epidemiology and Public Health, University College London, London, United Kingdom
| | - Benoit Lepage
- UMR LEASP, Université de Toulouse III, UPS, Inserm, Toulouse, France
| | - Thierry Lang
- UMR LEASP, Université de Toulouse III, UPS, Inserm, Toulouse, France
| | - Richard Layte
- Department of Sociology, School of Social Sciences and Philosophy, Trinity College Dublin, Dublin, Ireland
| | - Frances MacGuire
- Department of Epidemiology and Public Health, University College London, London, United Kingdom
| | - Johan P Mackenbach
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Michael Marmot
- Department of Epidemiology and Public Health, University College London, London, United Kingdom
| | - Cathal McCrory
- Department of Medical Gerontology, Trinity College Dublin, Dublin, Ireland
| | - Roger L Milne
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, VIC, Australia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC, Australia
- Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Melbourne, VIC, Australia
| | - Peter Muennig
- Mailman School of Public Health, Columbia University, New York, NY, United States
| | - Wilma Nusselder
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Dusan Petrovic
- Center for Primary Care and Public Health (UNISANTE), University of Lausanne, Lausanne, Switzerland
| | - Silvia Polidoro
- Molecular Epidemiology and Exposomics Unit, Italian Institute for Genomic Medicine, Turin, Italy
| | - Fulvio Ricceri
- Department of Clinical Science & Biology, Turin University Medical School, Turin, Italy
- Department of Epidemiology, ASL TO3, Turin, Italy
| | - Oliver Robinson
- Department of Epidemiology and Biostatistics, Imperial College London, London, United Kingdom
| | - Silvia Stringhini
- Unit of Population Epidemiology, Division of Primary Care, Geneva University Hospitals, Geneva, Switzerland
| | - Marie Zins
- UMS 011 Inserm - UVSQ ≪ Cohortes épidémiologiques en population ≫, Villejuif, France
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16
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Johnson AA, Shokhirev MN, Shoshitaishvili B. Revamping the evolutionary theories of aging. Ageing Res Rev 2019; 55:100947. [PMID: 31449890 DOI: 10.1016/j.arr.2019.100947] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Revised: 07/20/2019] [Accepted: 08/21/2019] [Indexed: 01/04/2023]
Abstract
Radical lifespan disparities exist in the animal kingdom. While the ocean quahog can survive for half a millennium, the mayfly survives for less than 48 h. The evolutionary theories of aging seek to explain why such stark longevity differences exist and why a deleterious process like aging evolved. The classical mutation accumulation, antagonistic pleiotropy, and disposable soma theories predict that increased extrinsic mortality should select for the evolution of shorter lifespans and vice versa. Most experimental and comparative field studies conform to this prediction. Indeed, animals with extreme longevity (e.g., Greenland shark, bowhead whale, giant tortoise, vestimentiferan tubeworms) typically experience minimal predation. However, data from guppies, nematodes, and computational models show that increased extrinsic mortality can sometimes lead to longer evolved lifespans. The existence of theoretically immortal animals that experience extrinsic mortality - like planarian flatworms, panther worms, and hydra - further challenges classical assumptions. Octopuses pose another puzzle by exhibiting short lifespans and an uncanny intelligence, the latter of which is often associated with longevity and reduced extrinsic mortality. The evolutionary response to extrinsic mortality is likely dependent on multiple interacting factors in the organism, population, and ecology, including food availability, population density, reproductive cost, age-mortality interactions, and the mortality source.
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Affiliation(s)
| | - Maxim N Shokhirev
- Razavi Newman Integrative Genomics and Bioinformatics Core, The Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Boris Shoshitaishvili
- Division of Literatures, Cultures, and Languages, Stanford University, Stanford, CA, United States
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17
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Cohen AA, Coste CFD, Li X, Bourg S, Pavard S. Are trade‐offs really the key drivers of ageing and life span? Funct Ecol 2019. [DOI: 10.1111/1365-2435.13444] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alan A. Cohen
- Groupe de recherche PRIMUS Department of Family Medicine University of Sherbrooke Sherbrooke QC Canada
| | - Christophe F. D. Coste
- Center for Biodiversity Dynamics Norwegian University of Science and Technology Trondheim Norway
- Unité Eco‐anthropologie (EA) Muséum National d'Histoire Naturelle CNRS 7206 Université Paris Diderot Paris France
| | - Xiang‐Yi Li
- Institute of Biology University of Neuchâtel Neuchâtel Switzerland
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich Switzerland
| | - Salomé Bourg
- CNRS Laboratoire de Biométrie et Biologie Évolutive UMR5558 Université Lyon 1 Villeurbanne France
| | - Samuel Pavard
- Unité Eco‐anthropologie (EA) Muséum National d'Histoire Naturelle CNRS 7206 Université Paris Diderot Paris France
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18
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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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19
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Vineis P, Kelly-Irving M. Biography and biological capital. Eur J Epidemiol 2019; 34:979-982. [PMID: 31342230 DOI: 10.1007/s10654-019-00539-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 07/18/2019] [Indexed: 01/19/2023]
Abstract
At the crossroads between sciences, epidemiology brings together the social and the biological to examine social inequalities in health. The concept of biological capital represents the accumulated history of biological experiences, alongside the other forms of accumulated capital, notably cultural, economic and social. The ability to access the three other forms of individual capital and therefore position in life depends on inherited biological health/skills, epigenetic imprinting and the accumulation of embodied biological changes that make an individual more or less successful in life. We present results from analyses carried out within the Lifepath consortium, showing that the socioeconomic environment, from early life and over the lifecourse, is an important risk factor for health and partly works through its effects on biological mechanisms. We show that socially stratified pre-disease states related to ageing may be examined using biomarkers, and help underline areas and mechanisms to promote healthy ageing.
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Affiliation(s)
- Paolo Vineis
- School of Public Health, MRC Centre for Environment and Health, Imperial College, Norfolk Place, London, W21PG, UK. .,Italian Institute for Genomic Medicine, Turin, Italy.
| | - Michelle Kelly-Irving
- LEASP, UMR 1027, Inserm-Université Toulouse III Paul Sabatier, 31000, Toulouse, France
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20
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Bretman A, Fricke C. Exposure to males, but not receipt of sex peptide, accelerates functional ageing in female fruit flies. Funct Ecol 2019. [DOI: 10.1111/1365-2435.13339] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Amanda Bretman
- School of Biology, Faculty of Biological Sciences University of Leeds Leeds UK
| | - Claudia Fricke
- Institute for Evolution and Biodiversity University of Muenster Muenster Germany
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21
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Ben-Ami F. Host Age Effects in Invertebrates: Epidemiological, Ecological, and Evolutionary Implications. Trends Parasitol 2019; 35:466-480. [PMID: 31003758 DOI: 10.1016/j.pt.2019.03.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/19/2019] [Accepted: 03/21/2019] [Indexed: 12/26/2022]
Abstract
In most species, variation in age among individuals is the strongest and most visible form of phenotypic variation. Individual-level age effects on disease traits, caused by differences in the age at exposure of the host or its parents, have been widely documented in invertebrates. They can influence diverse traits, such as host susceptibility, virulence, parasite reproduction and further transmission, and may cascade to the population level, influencing disease prevalence and within-host competition. Here, I summarize what is known about the relationship between individual-level age/stage effects and infectious disease in invertebrates. I also attempt to link age effects to the theory of aging (senescence), and highlight the importance of population age structure to disease epidemiology and evolution. I conclude by identifying gaps in our understanding of individual- and population-level age effects in invertebrates. As the age structure of populations varies across space and time, age effects have strong epidemiological, ecological, and evolutionary implications for explaining variation in infectious diseases of invertebrates.
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Affiliation(s)
- Frida Ben-Ami
- School of Zoology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.
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22
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Vega‐Trejo R, Fox RJ, Iglesias‐Carrasco M, Head ML, Jennions MD. The effects of male age, sperm age and mating history on ejaculate senescence. Funct Ecol 2019. [DOI: 10.1111/1365-2435.13305] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Regina Vega‐Trejo
- Division of Ecology and Evolution, Research School of Biology Australian National University Canberra Australian Capital Territory Australia
- Department of Zoology Stockholm University Stockholm Sweden
| | - Rebecca J. Fox
- Division of Ecology and Evolution, Research School of Biology Australian National University Canberra Australian Capital Territory Australia
| | - Maider Iglesias‐Carrasco
- Division of Ecology and Evolution, Research School of Biology Australian National University Canberra Australian Capital Territory Australia
| | - Megan L. Head
- Division of Ecology and Evolution, Research School of Biology Australian National University Canberra Australian Capital Territory Australia
| | - Michael D. Jennions
- Division of Ecology and Evolution, Research School of Biology Australian National University Canberra Australian Capital Territory Australia
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23
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Shi M, Zhou H, Lei M, Chen L, Zellmer L, He Y, Yang W, Xu N, Liao DJ. Spontaneous Cancers, But Not Many Induced Ones in Animals, Resemble Semi-New Organisms that Possess a Unique Programmed Cell Death Mode Different from Apoptosis, Senescent Death, Necrosis and Stress-Induced Cell Death. J Cancer 2018; 9:4726-4735. [PMID: 30588258 PMCID: PMC6299389 DOI: 10.7150/jca.26502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 09/11/2018] [Indexed: 01/26/2023] Open
Abstract
There are four basic cell death modes in animals, i.e. physiological senescent death (SD) and apoptosis as well as pathological necrosis and stress-induced cell death (SICD). There have been numerous publications describing “apoptosis” in cancer, mostly focused on killing cancer cells using radio- or chemo-therapy, with few on exploring how cancer cells die naturally without such treatments. Spontaneous benign or malignant neoplasms are immortal and autonomous, but they still retain some allegiance to their parental tissue or organ and thus are still somewhat controlled by the patient's body. Because of these properties of immortality, semi-autonomy, and semi-allegiance to the patient's body, spontaneous tumors have no redundant cells and resemble “semi-new organisms” parasitizing the patients, becoming a unique tissue type possessing a hitherto unannotated cell death mode besides SD, apoptosis, necrosis and SICD. Particularly, apoptosis aims to expunge redundant cells, whereas this new mode does not. In contrast to spontaneous tumors, many histologically malignant tumors induced in experimental animals, before they reach an advanced stage, regress after withdrawal of the inducer. This mortal and non-autonomous nature disqualifies these animal lesions as authentic neoplasms and as semi-new organisms but makes them a good tissue type for apoptosis studies. Ruminating over cell death in spontaneous cancers and many inauthentic tumors induced in animals from these new slants makes us realize that “whether cancer cells undergo apoptosis” is not an easy question with a simple answer. Our answer is that cancer cells have an uncharacterized programmed cell death mode, which is not apoptosis.
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Affiliation(s)
- Mingjun Shi
- Department of Pathophysiology, Guizhou Medical University, Guiyang 550025, Guizhou Province, China
| | - Haiyan Zhou
- Clinical Research Center, Guizhou Medical University Hospital, Guiyang 550004, Guizhou Province, China
| | - Mingjuan Lei
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Lichan Chen
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Lucas Zellmer
- Masonic Cancer Center, University of Minnesota, 435 E. River Road, Minneapolis, MN 55455, USA
| | - Yan He
- Key Lab of Endemic and Ethnic Diseases of the Ministry of Education of China at Guizhou Medical University, Guiyang 550004, Guizhou Province, China
| | - Wenxiu Yang
- Department of Pathology, Guizhou Medical University Hospital, Guiyang 550004, Guizhou province, China
| | - Ningzhi Xu
- Laboratory of Cell and Molecular Biology & State Key Laboratory of Molecular Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100021, China
| | - Dezhong Joshua Liao
- Key Lab of Endemic and Ethnic Diseases of the Ministry of Education of China at Guizhou Medical University, Guiyang 550004, Guizhou Province, China.,Department of Pathology, Guizhou Medical University Hospital, Guiyang 550004, Guizhou province, China
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24
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Dou X, Chen L, Lei M, Zellmer L, Jia Q, Ling P, He Y, Yang W, Liao DJ. Evaluating the Remote Control of Programmed Cell Death, with or without a Compensatory Cell Proliferation. Int J Biol Sci 2018; 14:1800-1812. [PMID: 30443184 PMCID: PMC6231223 DOI: 10.7150/ijbs.26962] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/24/2018] [Indexed: 12/23/2022] Open
Abstract
Organisms and their different component levels, whether organelle, cellular or other, come by birth and go by death, and the deaths are often balanced by new births. Evolution on the one hand has built demise program(s) in cells of organisms but on the other hand has established external controls on the program(s). For instance, evolution has established death program(s) in animal cells so that the cells can, when it is needed, commit apoptosis or senescent death (SD) in physiological situations and stress-induced cell death (SICD) in pathological situations. However, these programmed cell deaths are not predominantly regulated by the cells that do the dying but, instead, are controlled externally and remotely by the cells' superior(s), i.e. their host tissue or organ or even the animal's body. Currently, it is still unclear whether a cell has only one death program or has several programs respectively controlling SD, apoptosis and SICD. In animals, apoptosis exterminates, in a physiological manner, healthy but no-longer needed cells to avoid cell redundancy, whereas suicidal SD and SICD, like homicidal necrosis, terminate ill but useful cells, which may be followed by regeneration of the live cells and by scar formation to heal the damaged organ or tissue. Therefore, “who dies” clearly differentiates apoptosis from SD, SICD and necrosis. In animals, apoptosis can occur only in those cell types that retain a lifelong ability of proliferation and never occurs in those cell types that can no longer replicate in adulthood. In cancer cells, SICD is strengthened, apoptosis is dramatically weakened while SD has been lost. Most published studies professed to be about apoptosis are actually about SICD, which has four basic and well-articulated pathways involving caspases or involving pathological alterations in the mitochondria, endoplasmic reticula, or lysosomes.
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Affiliation(s)
- Xixi Dou
- Key Laboratory of Biopharmaceuticals, Shandong Academy of Pharmaceutical Sciences, Jinan 250101, Shandong Province, P.R. China.,Technology Center, Shandong Freda Pharmaceutical Group, Jinan 250101, Shandong Province, P.R. China
| | - Lichan Chen
- College of Chemical Engineering, Huaqiao University, Xiamen 361021, Fujian Province, P.R. China
| | - Mingjuan Lei
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Lucas Zellmer
- Masonic Cancer Center, University of Minnesota, 435 E. River Road, Minneapolis, MN 55455, USA
| | - Qingwen Jia
- Key Laboratory of Biopharmaceuticals, Shandong Academy of Pharmaceutical Sciences, Jinan 250101, Shandong Province, P.R. China
| | - Peixue Ling
- Key Laboratory of Biopharmaceuticals, Shandong Academy of Pharmaceutical Sciences, Jinan 250101, Shandong Province, P.R. China.,Technology Center, Shandong Freda Pharmaceutical Group, Jinan 250101, Shandong Province, P.R. China
| | - Yan He
- Key Lab of Endemic and Ethnic Diseases of the Ministry of Education of China in Guizhou Medical University, Guiyang 550004, Guizhou Province, P.R. China
| | - Wenxiu Yang
- Department of Pathology, Guizhou Medical University Hospital, Guiyang 550004, Guizhou province, P.R. China
| | - Dezhong Joshua Liao
- Key Lab of Endemic and Ethnic Diseases of the Ministry of Education of China in Guizhou Medical University, Guiyang 550004, Guizhou Province, P.R. China.,Department of Pathology, Guizhou Medical University Hospital, Guiyang 550004, Guizhou province, P.R. China
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25
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Dańko MJ, Burger O, Argasiński K, Kozłowski J. Extrinsic Mortality Can Shape Life-History Traits, Including Senescence. Evol Biol 2018; 45:395-404. [PMID: 30459480 PMCID: PMC6223763 DOI: 10.1007/s11692-018-9458-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 06/07/2018] [Indexed: 11/24/2022]
Abstract
The Williams' hypothesis is one of the most widely known ideas in life history evolution. It states that higher adult mortality should lead to faster and/or earlier senescence. Theoretically derived gradients, however, do not support this prediction. Increased awareness of this fact has caused a crisis of misinformation among theorists and empirical ecologists. We resolve this crisis by outlining key issues in the measurement of fitness, assumptions of density dependence, and their effect on extrinsic mortality. The classic gradients apply only to a narrow range of ecological contexts where density-dependence is either absent or present but with unrealistic stipulations. Re-deriving the classic gradients, using a more appropriate measure of fitness and incorporating density, shows that broad ecological contexts exist where Williams' hypothesis is supported.
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Affiliation(s)
- Maciej J Dańko
- 1Max Planck Institute for Demographic Research, Rostock, Germany
| | - Oskar Burger
- 1Max Planck Institute for Demographic Research, Rostock, Germany
| | | | - Jan Kozłowski
- 3Institute of Environmental Sciences, Jagiellonian University, Krakow, Poland
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26
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Everman ER, Morgan TJ. Antagonistic pleiotropy and mutation accumulation contribute to age-related decline in stress response. Evolution 2018; 72:303-317. [PMID: 29214647 DOI: 10.1111/evo.13408] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 11/10/2017] [Accepted: 11/13/2017] [Indexed: 01/17/2023]
Abstract
As organisms age, the effectiveness of natural selection weakens, leading to age-related decline in fitness-related traits. The evolution of age-related changes associated with senescence is likely influenced by mutation accumulation (MA) and antagonistic pleiotropy (AP). MA predicts that age-related decline in fitness components is driven by age-specific sets of alleles, nonnegative genetic correlations within trait across age, and an increase in the coefficient of genetic variance. AP predicts that age-related decline in a trait is driven by alleles with positive effects on fitness in young individuals and negative effects in old individuals, and is expected to lead to negative genetic correlations within traits across age. We build on these predictions using an association mapping approach to investigate the change in additive effects of SNPs across age and among traits for multiple stress-response fitness-related traits, including cold stress with and without acclimation and starvation resistance. We found support for both MA and AP theories of aging in the age-related decline in stress tolerance. Our study demonstrates that the evolution of age-related decline in stress tolerance is driven by a combination of alleles that have age-specific additive effects, consistent with MA, as well as nonindependent and antagonistic genetic architectures characteristic of AP.
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Affiliation(s)
- Elizabeth R Everman
- Division of Biology, Kansas State University, Manhattan, Kansas 66506
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas 66045
| | - Theodore J Morgan
- Division of Biology, Kansas State University, Manhattan, Kansas 66506
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27
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Maklakov AA, Carlsson H, Denbaum P, Lind MI, Mautz B, Hinas A, Immler S. Antagonistically pleiotropic allele increases lifespan and late-life reproduction at the cost of early-life reproduction and individual fitness. Proc Biol Sci 2018; 284:rspb.2017.0376. [PMID: 28615498 DOI: 10.1098/rspb.2017.0376] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 05/15/2017] [Indexed: 01/03/2023] Open
Abstract
Evolutionary theory of ageing maintains that increased allocation to early-life reproduction results in reduced somatic maintenance, which is predicted to compromise longevity and late-life reproduction. This prediction has been challenged by the discovery of long-lived mutants with no loss of fecundity. The first such long-lived mutant was found in the nematode worm Caenorhabditis elegans Specifically, partial loss-of-function mutation in the age-1 gene, involved in the nutrient-sensing insulin/insulin-like growth factor signalling pathway, confers longevity, as well as increased resistance to pathogens and to temperature stress without appreciable fitness detriment. Here, we show that the long-lived age-1(hx546) mutant has reduced fecundity and offspring production in early-life, but increased fecundity, hatching success, and offspring production in late-life compared with wild-type worms under standard conditions. However, reduced early-life performance of long-lived mutant animals was not fully compensated by improved performance in late-life and resulted in reduced individual fitness. These results suggest that the age-1(hx546) allele has opposing effects on early-life versus late-life fitness in accordance with antagonistic pleiotropy (AP) and disposable soma theories of ageing. These findings support the theoretical conjecture that experimental studies based on standing genetic variation underestimate the importance of AP in the evolution of ageing.
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Affiliation(s)
- Alexei A Maklakov
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, Uppsala 752 36, Sweden .,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, Norfolk, UK
| | - Hanne Carlsson
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, Uppsala 752 36, Sweden
| | - Philip Denbaum
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, Uppsala 752 36, Sweden
| | - Martin I Lind
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, Uppsala 752 36, Sweden
| | - Brian Mautz
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, Uppsala 752 36, Sweden
| | - Andrea Hinas
- Department of Cell and Molecular Biology, Uppsala University, PO Box 596, Uppsala 75124, Sweden
| | - Simone Immler
- Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, Uppsala 752 36, Sweden.,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, Norfolk, UK
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28
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Gaillard JM, Lemaître JF. The Williams' legacy: A critical reappraisal of his nine predictions about the evolution of senescence. Evolution 2017; 71:2768-2785. [DOI: 10.1111/evo.13379] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 09/25/2017] [Accepted: 09/30/2017] [Indexed: 12/16/2022]
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29
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Dańko MJ, Burger O, Kozłowski J. Density-dependence interacts with extrinsic mortality in shaping life histories. PLoS One 2017; 12:e0186661. [PMID: 29049399 PMCID: PMC5648222 DOI: 10.1371/journal.pone.0186661] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 10/05/2017] [Indexed: 12/02/2022] Open
Abstract
The role of extrinsic mortality in shaping life histories is poorly understood. However, substantial evidence suggests that extrinsic mortality interacts with density-dependence in crucial ways. We develop a model combining Evolutionarily Stable Strategies with a projection matrix that allows resource allocation to growth, tissue repairs, and reproduction. Our model examines three cases, with density-dependence acting on: (i) mortality, (ii) fecundity, and (iii) production rate. We demonstrate that density-independent extrinsic mortality influences the rate of aging, age at maturity, growth rate, and adult size provided that density-dependence acts on fertility or juvenile mortality. However, density-independent extrinsic mortality has no effect on these life history traits when density-dependence acts on survival. We show that extrinsic mortality interacts with density-dependence via a compensation mechanism: the higher the extrinsic mortality the lower the strength of density-dependence. However, this compensation fully offsets the effect of extrinsic mortality only if density-dependence acts on survival independently of age. Both the age-pattern and the type of density-dependence are crucial for shaping life history traits.
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Affiliation(s)
- Maciej Jan Dańko
- Max Planck Institute for Demographic Research, Rostock, Germany
- * E-mail:
| | - Oskar Burger
- Max Planck Institute for Demographic Research, Rostock, Germany
| | - Jan Kozłowski
- Jagiellonian University, Institute of Environmental Sciences, Kraków, Poland
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30
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Reichard M. Evolutionary perspectives on ageing. Semin Cell Dev Biol 2017; 70:99-107. [DOI: 10.1016/j.semcdb.2017.05.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 05/19/2017] [Accepted: 05/23/2017] [Indexed: 02/07/2023]
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31
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Arnqvist G, Stojković B, Rönn JL, Immonen E. The pace‐of‐life: A sex‐specific link between metabolic rate and life history in bean beetles. Funct Ecol 2017. [DOI: 10.1111/1365-2435.12927] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Göran Arnqvist
- Animal EcologyDepartment of Ecology and GeneticsEvolutionary Biology CentreUppsala University Uppsala Sweden
| | - Biljana Stojković
- Department of Evolutionary BiologyInstitute for Biological ResearchUniversity of Belgrade Belgrade Serbia
- Institute of ZoologyFaculty of BiologyUniversity of Belgrade Belgrade Serbia
| | - Johanna L. Rönn
- Animal EcologyDepartment of Ecology and GeneticsEvolutionary Biology CentreUppsala University Uppsala Sweden
| | - Elina Immonen
- Animal EcologyDepartment of Ecology and GeneticsEvolutionary Biology CentreUppsala University Uppsala Sweden
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32
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A mild cold stress that increases resistance to heat lowers FOXO translocation in Drosophila melanogaster. Biogerontology 2017; 18:791-801. [DOI: 10.1007/s10522-017-9722-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 06/29/2017] [Indexed: 10/19/2022]
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33
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Weadick CJ, Sommer RJ. Unexpected sex-specific post-reproductive lifespan in the free-living nematode Pristionchus exspectatus. Evol Dev 2017; 18:297-307. [PMID: 27870213 DOI: 10.1111/ede.12206] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Patterns of senescence (or aging) can vary among life history traits and between the sexes, providing an opportunity to study variation in the aging process within a single species. We previously found that females of the nematode Pristionchus exspectatus outlive males by a substantial margin under laboratory conditions. Here, we show that sex-specific reproductive senescence unfolds in the opposite direction in this species, resulting in a prolonged period of female-specific post-reproductive survival: females lost the ability to reproduce at approximately 4.7 weeks despite a median lifespan of about 12.3 weeks under lab conditions, whereas males lost the ability to reproduce at approximately 6.6 weeks, roughly in line with their median lifespan of around 7.6 weeks. Interestingly, somatic senescence (declining crawling speed) only explained reproductive senescence in males, whereas females lost the ability to reproduce regardless of condition. However, we found that housing females with males significantly increased their mortality rate, indicating that female-specific post-reproductive survival is unlikely to occur in the wild. We discuss our results in light of evolutionary theories of post-reproductive survival and previous studies of nematode behavioral ecology, arguing that premature reproductive senescence may stem from sex-specific condition-dependent survival during the reproductive period. Given the proven lab tractability of Prisitonchus nematodes, our findings provide a foundation for integrative research that combines evolutionary ecology and molecular genetics in the study of sex-specific senescence and post-reproductive survival.
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Affiliation(s)
- Cameron J Weadick
- Department of Integrative Evolutionary Biology, Max Planck Institute for Developmental Biology, Spemmanstraße 37, Tübingen, 72076, Germany
| | - Ralf J Sommer
- Department of Integrative Evolutionary Biology, Max Planck Institute for Developmental Biology, Spemmanstraße 37, Tübingen, 72076, Germany
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34
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Millan MJ. Linking deregulation of non-coding RNA to the core pathophysiology of Alzheimer's disease: An integrative review. Prog Neurobiol 2017; 156:1-68. [PMID: 28322921 DOI: 10.1016/j.pneurobio.2017.03.004] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 03/09/2017] [Accepted: 03/09/2017] [Indexed: 02/06/2023]
Abstract
The human genome encodes a vast repertoire of protein non-coding RNAs (ncRNA), some specific to the brain. MicroRNAs, which interfere with the translation of target mRNAs, are of particular interest since their deregulation has been implicated in neurodegenerative disorders like Alzheimer's disease (AD). However, it remains challenging to link the complex body of observations on miRNAs and AD into a coherent framework. Using extensive graphical support, this article discusses how a diverse panoply of miRNAs convergently and divergently impact (and are impacted by) core pathophysiological processes underlying AD: neuroinflammation and oxidative stress; aberrant generation of β-amyloid-42 (Aβ42); anomalies in the production, cleavage and post-translational marking of Tau; impaired clearance of Aβ42 and Tau; perturbation of axonal organisation; disruption of synaptic plasticity; endoplasmic reticulum stress and the unfolded protein response; mitochondrial dysfunction; aberrant induction of cell cycle re-entry; and apoptotic loss of neurons. Intriguingly, some classes of miRNA provoke these cellular anomalies, whereas others act in a counter-regulatory, protective mode. Moreover, changes in levels of certain species of miRNA are a consequence of the above-mentioned anomalies. In addition to miRNAs, circular RNAs, piRNAs, long non-coding RNAs and other types of ncRNA are being increasingly implicated in AD. Overall, a complex mesh of deregulated and multi-tasking ncRNAs reciprocally interacts with core pathophysiological mechanisms underlying AD. Alterations in ncRNAs can be detected in CSF and the circulation as well as the brain and are showing promise as biomarkers, with the ultimate goal clinical exploitation as targets for novel modes of symptomatic and course-altering therapy.
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Affiliation(s)
- Mark J Millan
- Centre for Therapeutic Innovation in Neuropsychiatry, institut de recherche Servier, 125 chemin de ronde, 78290 Croissy sur Seine, France.
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35
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Lind MI, Chen H, Meurling S, Guevara Gil AC, Carlsson H, Zwoinska MK, Andersson J, Larva T, Maklakov AA. Slow development as an evolutionary cost of long life. Funct Ecol 2017. [DOI: 10.1111/1365-2435.12840] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Martin I. Lind
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | - Hwei‐yen Chen
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | - Sara Meurling
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | | | - Hanne Carlsson
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | - Martyna K. Zwoinska
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | - Johan Andersson
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | - Tuuli Larva
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | - Alexei A. Maklakov
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
- School of Biological Sciences University of East Anglia Norwich Research Park Norwich NR4 7TJ UK
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36
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Hughes KA, Leips J. Pleiotropy, constraint, and modularity in the evolution of life histories: insights from genomic analyses. Ann N Y Acad Sci 2017; 1389:76-91. [PMID: 27936291 PMCID: PMC5318229 DOI: 10.1111/nyas.13256] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 08/10/2016] [Accepted: 08/22/2016] [Indexed: 12/20/2022]
Abstract
Multicellular organisms display an enormous range of life history (LH) strategies and present an evolutionary conundrum; despite strong natural selection, LH traits are characterized by high levels of genetic variation. To understand the evolution of life histories and maintenance of this variation, the specific phenotypic effects of segregating alleles and the genetic networks in which they act need to be elucidated. In particular, the extent to which LH evolution is constrained by the pleiotropy of alleles contributing to LH variation is generally unknown. Here, we review recent empirical results that shed light on this question, with an emphasis on studies employing genomic analyses. While genome-scale analyses are increasingly practical and affordable, they face limitations of genetic resolution and statistical power. We describe new research approaches that we believe can produce new insights and evaluate their promise and applicability to different kinds of organisms. Two approaches seem particularly promising: experiments that manipulate selection in multiple dimensions and measure phenotypic and genomic response and analytical approaches that take into account genome-wide associations between markers and phenotypes, rather than applying a traditional marker-by-marker approach.
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Affiliation(s)
- Kimberly A. Hughes
- Department of Biological Science, Florida State University, Tallahassee, Florida
| | - Jeff Leips
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, Maryland
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37
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Metal-based superoxide dismutase and catalase mimics reduce oxidative stress biomarkers and extend life span of Saccharomyces cerevisiae. Biochem J 2017; 474:301-315. [DOI: 10.1042/bcj20160480] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 11/10/2016] [Accepted: 11/14/2016] [Indexed: 11/17/2022]
Abstract
Aging is a natural process characterized by several biological changes. In this context, oxidative stress appears as a key factor that leads cells and organisms to severe dysfunctions and diseases. To cope with reactive oxygen species and oxidative-related damage, there has been increased use of superoxide dismutase (SOD)/catalase (CAT) biomimetic compounds. Recently, we have shown that three metal-based compounds {[Fe(HPClNOL)Cl2]NO3, [Cu(HPClNOL)(CH3CN)](ClO4)2 and Mn(HPClNOL)(Cl)2}, harboring in vitro SOD and/or CAT activities, were critical for protection of yeast cells against oxidative stress. In this work, treating Saccharomyces cerevisiae with these SOD/CAT mimics (25.0 µM/1 h), we highlight the pivotal role of these compounds to extend the life span of yeast during chronological aging. Evaluating lipid and protein oxidation of aged cells, it becomes evident that these mimics extend the life expectancy of yeast mainly due to the reduction in oxidative stress biomarkers. In addition, the treatment of yeast cells with these mimics regulated the amounts of lipid droplet occurrence, consistent with the requirement and protection of lipids for cell integrity during aging. Concerning SOD/CAT mimics uptake, using inductively coupled plasma mass spectrometry, we add new evidence that these complexes, besides being bioabsorbed by S. cerevisiae cells, can also affect metal homeostasis. Finally, our work presents a new application for these SOD/CAT mimics, which demonstrate a great potential to be employed as antiaging agents. Taken together, these promising results prompt future studies concerning the relevance of administration of these molecules against the emerging aging-related diseases such as Parkinson's, Alzheimer's and Huntington's.
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38
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Brooks RC, Garratt MG. Life history evolution, reproduction, and the origins of sex-dependent aging and longevity. Ann N Y Acad Sci 2016; 1389:92-107. [PMID: 28009055 DOI: 10.1111/nyas.13302] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Revised: 11/02/2016] [Accepted: 11/07/2016] [Indexed: 12/19/2022]
Abstract
Males and females in many species differ in how they age and how long they live. These differences have motivated much research, concerning both their evolution and the underlying mechanisms that cause them. We review how differences in male and female life histories have evolved to shape patterns of aging and some of the mechanisms and pathways involved. We pay particular attention to three areas where considerable potential for synergy between mechanistic and evolutionary research exists: (1) the role of estrogens, androgens, the growth hormone/insulin-like growth factor 1 pathway, and the mechanistic target of rapamycin signaling pathway in sex-dependent growth and reproduction; (2) sexual conflict over mating rate and fertility, and how mate presence or mating can become an avenue for males and females to directly affect each other's life span; and (3) the link between dietary restriction and aging, and the emerging understanding that only the restriction of certain nutrients is involved and that this is linked to reproduction. We suggest that ideas about life histories, sex-dependent selection, and sexual conflict can inform and be informed by the ever more refined and complex understanding of the mechanisms that cause aging.
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Affiliation(s)
- Robert C Brooks
- Evolution & Ecology Research Centre, and School of Biological, Earth and Environmental Sciences, UNSW Australia, Kensington, Sydney, New South Wales, Australia
| | - Michael G Garratt
- Evolution & Ecology Research Centre, and School of Biological, Earth and Environmental Sciences, UNSW Australia, Kensington, Sydney, New South Wales, Australia.,Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan
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39
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Blažek R, Polačik M, Kačer P, Cellerino A, Řežucha R, Methling C, Tomášek O, Syslová K, Terzibasi Tozzini E, Albrecht T, Vrtílek M, Reichard M. Repeated intraspecific divergence in life span and aging of African annual fishes along an aridity gradient. Evolution 2016; 71:386-402. [PMID: 27859247 DOI: 10.1111/evo.13127] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 11/07/2016] [Accepted: 11/09/2016] [Indexed: 01/22/2023]
Abstract
Life span and aging are substantially modified by natural selection. Across species, higher extrinsic (environmentally related) mortality (and hence shorter life expectancy) selects for the evolution of more rapid aging. However, among populations within species, high extrinsic mortality can lead to extended life span and slower aging as a consequence of condition-dependent survival. Using within-species contrasts of eight natural populations of Nothobranchius fishes in common garden experiments, we demonstrate that populations originating from dry regions (with short life expectancy) had shorter intrinsic life spans and a greater increase in mortality with age, more pronounced cellular and physiological deterioration (oxidative damage, tumor load), and a faster decline in fertility than populations from wetter regions. This parallel intraspecific divergence in life span and aging was not associated with divergence in early life history (rapid growth, maturation) or pace-of-life syndrome (high metabolic rates, active behavior). Variability across four study species suggests that a combination of different aging and life-history traits conformed with or contradicted the predictions for each species. These findings demonstrate that variation in life span and functional decline among natural populations are linked, genetically underpinned, and can evolve relatively rapidly.
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Affiliation(s)
- Radim Blažek
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Květná 8, 603 65, Brno, Czech Republic
| | - Matej Polačik
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Květná 8, 603 65, Brno, Czech Republic
| | - Petr Kačer
- Laboratory of Medicinal Diagnostics, Department of Organic Technology, University of Chemistry and Technology, Technická 5, 166 28, Prague, Czech Republic
| | - Alessandro Cellerino
- Bio@SNS, Scuola Normale Superiore, Department of Neurosciences, Piazza dei Cavalieri 7, 56126, Pisa, Italy.,Fritz Lipmann Institute for Age Research, Leibniz Institute, Beutenbergstr. 11, D-07745, Jena, Germany
| | - Radomil Řežucha
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Květná 8, 603 65, Brno, Czech Republic
| | - Caroline Methling
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Květná 8, 603 65, Brno, Czech Republic
| | - Oldřich Tomášek
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Květná 8, 603 65, Brno, Czech Republic.,Department of Zoology, Faculty of Sciences, Charles University in Prague, Viničná 7, 128 44, Praha, Czech Republic
| | - Kamila Syslová
- Laboratory of Medicinal Diagnostics, Department of Organic Technology, University of Chemistry and Technology, Technická 5, 166 28, Prague, Czech Republic
| | - Eva Terzibasi Tozzini
- Bio@SNS, Scuola Normale Superiore, Department of Neurosciences, Piazza dei Cavalieri 7, 56126, Pisa, Italy
| | - Tomáš Albrecht
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Květná 8, 603 65, Brno, Czech Republic.,Department of Zoology, Faculty of Sciences, Charles University in Prague, Viničná 7, 128 44, Praha, Czech Republic
| | - Milan Vrtílek
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Květná 8, 603 65, Brno, Czech Republic
| | - Martin Reichard
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Květná 8, 603 65, Brno, Czech Republic
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40
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Zajitschek F, Zajitschek SRK, Canton C, Georgolopoulos G, Friberg U, Maklakov AA. Evolution under dietary restriction increases male reproductive performance without survival cost. Proc Biol Sci 2016; 283:20152726. [PMID: 26911958 DOI: 10.1098/rspb.2015.2726] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Dietary restriction (DR), a reduction in nutrient intake without malnutrition, is the most reproducible way to extend lifespan in a wide range of organisms across the tree of life, yet the evolutionary underpinnings of the DR effect on lifespan are still widely debated. The leading theory suggests that this effect is adaptive and results from reallocation of resources from reproduction to somatic maintenance, in order to survive periods of famine in nature. However, such response would cease to be adaptive when DR is chronic and animals are selected to allocate more resources to reproduction. Nevertheless, chronic DR can also increase the strength of selection resulting in the evolution of more robust genotypes. We evolved Drosophila melanogaster fruit flies on 'DR', 'standard' and 'high' adult diets in replicate populations with overlapping generations. After approximately 25 generations of experimental evolution, male 'DR' flies had higher fitness than males from 'standard' and 'high' populations. Strikingly, this increase in reproductive success did not come at a cost to survival. Our results suggest that sustained DR selects for more robust male genotypes that are overall better in converting resources into energy, which they allocate mostly to reproduction.
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Affiliation(s)
- Felix Zajitschek
- School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Uppsala 75236, Sweden
| | - Susanne R K Zajitschek
- Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Uppsala 75236, Sweden Doñana Biological Station, Spanish Research Council CSIC, c/ Americo Vespucio, s/n, Isla de la Cartuja, 41092 Sevilla, Spain
| | - Cindy Canton
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Uppsala 75236, Sweden
| | - Grigorios Georgolopoulos
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Uppsala 75236, Sweden
| | - Urban Friberg
- Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Uppsala 75236, Sweden IFM Biology, AVIAN Behavioural, Genomics and Physiology Group, Linköping University, Linköping 58183, Sweden
| | - Alexei A Maklakov
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Uppsala 75236, Sweden
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41
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Adler MI, Telford M, Bonduriansky R. Phenotypes optimized for early‐life reproduction exhibit faster somatic deterioration with age, revealing a latent cost of high condition. J Evol Biol 2016; 29:2436-2446. [DOI: 10.1111/jeb.12968] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 07/27/2016] [Accepted: 08/14/2016] [Indexed: 01/19/2023]
Affiliation(s)
- M. I. Adler
- Evolution & Ecology Research Centre and School of Biological Earth and Environmental Sciences University of New South Wales Sydney NSW Australia
| | - M. Telford
- Evolution & Ecology Research Centre and School of Biological Earth and Environmental Sciences University of New South Wales Sydney NSW Australia
- Institut de Biologia Evolutiva Universitat Pompeu Fabra Barcelona Spain
| | - R. Bonduriansky
- Evolution & Ecology Research Centre and School of Biological Earth and Environmental Sciences University of New South Wales Sydney NSW Australia
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42
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Burger O, Missov TI. Evolutionary theory of ageing and the problem of correlated Gompertz parameters. J Theor Biol 2016; 408:34-41. [PMID: 27503574 DOI: 10.1016/j.jtbi.2016.08.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 07/11/2016] [Accepted: 08/05/2016] [Indexed: 12/27/2022]
Abstract
The Gompertz mortality model is often used to evaluate evolutionary theories of ageing, such as the Medawar-Williams' hypothesis that high extrinsic mortality leads to faster ageing. However, fits of the Gompertz mortality model to data often find the opposite result that mortality is negatively correlated with the rate of ageing. This negative correlation has been independently discovered in several taxa and is known in actuarial studies of ageing as the Strehler-Mildvan correlation. We examine the role of mortality selection in determining late-life variation in susceptibility to death, which has been suggested to be the cause of this negative correlation. We demonstrate that fixed-frailty models that account for heterogeneity in frailty do not remove the correlation and that the correlation is an inherent statistical property of the Gompertz distribution. Linking actuarial and biological rates of ageing will continue to be a pressing challenge, but the Strehler-Mildvan correlation itself should not be used to diagnose any biological, physiological, or evolutionary process. These findings resolve some key tensions between theory and data that affect evolutionary and biological studies of ageing and mortality. Tests of evolutionary theories of ageing should include direct measures of physiological performance or condition.
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Affiliation(s)
- Oskar Burger
- Max Planck Institute for Demographic Research, Konrad-Zuse-Str. 1, 18057, Rostock, Germany.
| | - Trifon I Missov
- Max Planck Institute for Demographic Research, Konrad-Zuse-Str. 1, 18057, Rostock, Germany; Mathematical Demography, University of Rostock, Ulmenstr. 69, 18057 Rostock, Germany
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Curtsinger JW. Retired flies, hidden plateaus, and the evolution of senescence in Drosophila melanogaster. Evolution 2016; 70:1297-306. [PMID: 27166620 DOI: 10.1111/evo.12946] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Revised: 04/24/2016] [Accepted: 05/05/2016] [Indexed: 01/12/2023]
Abstract
Late-life plateaus in age-specific mortality have been an evolutionary and biodemographic puzzle for decades. Although classic theory on the evolution of senescence predicts late-life walls of death, observations in experimental organisms document the opposite trend: a slowing in the rate of increase of mortality at advanced ages. Here, I analyze published life-history data on individual Drosophila melanogaster females and argue for a fundamental change in our understanding of mortality in this important model system. Mortality plateaus are not, as widely assumed, exclusive to late life, and are not explained by population heterogeneity-they are intimately connected to individual fecundity. Female flies begin adult life in the working stage, a period of active oviposition and low but accelerating mortality. Later they transition to the retired stage, a terminal period characterized by limited fecundity and relatively constant mortality. Because ages of transition differ between flies, age-synchronized cohorts contain a mix of working and retired flies. Early- and mid-life plateaus are obscured by the presence of working flies, but can be detected when cohorts are stratified by retirement status. Stage-specificity may be an important component of Drosophila life-history evolution.
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Affiliation(s)
- James W Curtsinger
- Department of Ecology, Evolution, and Behavior, University of Minnesota, Twin Cities, St. Paul, Minnesota, 55108.
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Chen HY, Spagopoulou F, Maklakov AA. Evolution of male age-specific reproduction under differential risks and causes of death: males pay the cost of high female fitness. J Evol Biol 2016; 29:848-56. [DOI: 10.1111/jeb.12833] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 01/12/2016] [Accepted: 01/15/2016] [Indexed: 11/28/2022]
Affiliation(s)
- H.-y. Chen
- Ageing Research Group; Department of Animal Ecology; Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
| | - F. Spagopoulou
- Ageing Research Group; Department of Animal Ecology; Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
| | - A. A. Maklakov
- Ageing Research Group; Department of Animal Ecology; Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
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Weadick CJ, Sommer RJ. Mating System Transitions Drive Life Span Evolution in Pristionchus Nematodes. Am Nat 2016; 187:517-31. [PMID: 27028079 DOI: 10.1086/685283] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Interactions between the sexes influence evolution at many scales, but not all animal species conform to the familiar male-female (dioecious) mating system; such taxa are powerful tools for studying the evolutionary importance of sexual selection and conflict on all manner of life-history traits, including longevity. We tested for an effect of mating system on adult life span in Pristionchus nematodes, where self-fertile hermaphrodites have replaced females multiple times independently throughout the genus (androdioecy). By measuring adult life span for 11 species (6 dioecious, 5 androdioecious), we found that life span is considerably shorter in hermaphrodites relative to closely related females. This effect is not a cost of reproduction; brood size did not reliably trade off with life span in self-fertilizing hermaphrodites or in mated females. Furthermore, we found that sexual dimorphism in life span varied among dioecious species, with females generally outliving males. Finally, we documented intraspecific variation for life span and cuticular disease (blistering) prevalence in Pristionchus pacificus, a model system for evolutionary-developmental biology. This work demonstrates that mating system transitions and life span evolution are linked in Pristionchus nematodes and provides a foundation for future comparative and mechanistic studies of aging in this genus.
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Le Bourg É. Life-time protection against severe heat stress by exposing young Drosophila melanogaster flies to a mild cold stress. Biogerontology 2015; 17:409-15. [PMID: 26704618 DOI: 10.1007/s10522-015-9629-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 12/18/2015] [Indexed: 10/22/2022]
Abstract
Previous studies in the laboratory of the author have shown that subjecting flies to a mild stress (e.g. a cold stress) during the first 2 weeks of adult life can increase lifespan and resistance to severe stresses (e.g. heat and fungal infection) at 6 weeks of age (ca the mean lifespan at 25 °C). This result could either show that a mild stress protects flies against severe stress for the entire life or for a duration of 4 weeks. To clarify the issue, young flies living at 25 °C were pretreated with a cold stress and thereafter transferred at 19 or 22 °C, which increases lifespan. The mild cold stress protected these flies from heat at ages when flies kept at 25 °C are dead, i.e. at 10 weeks of age or 8 weeks after the end of cold stress. Thus, a mild stress protects flies for life, even if the duration of life is increased. Because temperature can strongly vary from day to day in the wild, and lifespan of flies too, it would be a selective advantage if the ability to survive a strong stress after having been subjected to a mild stress would be maintained not only for a few days but for life, whatever its duration could be. If flies would be subjected to a mild stress when living at 25 °C, a temperature change from e.g. 25 to 22 °C would increase their lifespan and they could survive a strong stress at an age when flies kept at 25 °C are dead.
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Affiliation(s)
- Éric Le Bourg
- Centre de Recherches sur la Cognition Animale, Centre de Biologie Intégrative, Université de Toulouse, CNRS, UPS, Toulouse, France.
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