Does oxidative stress shorten telomeres in vivo? A meta-analysis

Ageing Research Reviews, Journal Year: 2023, Volume and Issue: 85, P. 101854 - 101854

Published: Jan. 17, 2023

Telomere attrition is considered a hallmark of ageing. Untangling the proximate causes telomere may therefore reveal important aspects about ageing process. In landmark paper in 2002 Thomas von Zglinicki demonstrated that oxidative stress accelerates cell culture. next 20 years, became firmly embedded into modern theories and attrition. However, recent surge vivo studies reveals an inconsistent pattern questioning unequivocal role length (henceforth referred to as dynamics), living organisms. Here we report results first formal meta-analysis on association between dynamics vivo, representing 37 studies, 4969 individuals, 18,677 correlational measurements. The overall correlation markers was indistinguishable from zero (r = 0.027). This result independent type marker, dynamic, or taxonomic group. measurement method affected analysis subset TRF-based showed significant 0.09), supporting prediction more pronounced short-lived species during adult life phase, when becomes apparent. We then performed additional interventional (n 7) manipulating stress. revealed effect treatment (d=0.36). Our findings provide new support for hypothesis

Language: Английский

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Biological clocks as age estimation markers in animals: a systematic review and meta‐analysis

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Journal Year: 2023, Volume and Issue: 98(6), P. 1972 - 2011

Published: June 25, 2023

ABSTRACT Various biological attributes associated with individual fitness in animals change predictably over the lifespan of an organism. Therefore, study animal ecology and work conservationists frequently relies upon ability to assign functionally relevant age classes model population fitness. Several approaches have been applied determining and, while these methods proved useful, they are not without limitations often lack standardisation or only applicable specific species. For reasons, scientists explored potential use clocks towards creating a universal age‐determination method. Two clocks, tooth layer annulation otolith layering found appeal. Both highly invasive most appropriate for post‐mortem age‐at‐death estimation. More recently, cellular ageing previously humans adapted studying less‐invasive molecular age. Here, we review two such methods, assessment methylation telomere length, describing ( i ) what are, ii how age, providing iii summary meta‐analysis studies that their utility determination. We both studied across multiple vertebrate classes, however, were used before length has modelled nearly twice as many studies. Telomere included related changes stress responses illustrated is sensitive environmental social stressors absence repair mechanisms telomerase alternative lengthening modes, lacks recover. Methylation studies, also detecting sensitivity toxins, recover from stresses after period accelerated ageing, likely due constitutive expression reactivation enzymes DNA methyl transferases. parentally heritable features, but mode inheritance differs among taxa may relate heterogamy. Our more than 40 species common although analyses at least 60 age‐estimation models. outperforms terms predictive power evidenced effect sizes (more double observed telomeres) smaller prediction intervals. produced correlation models using similar sample able classify individuals into young, middle, old high accuracy. illustrate well suited do suffer significantly variation differences species, genome size, karyotype, tissue type rather quantitative method, patterns inheritance, factors should be main considerations. Thus, provided complex affecting measured trait can accounted for, promising targets develop biomarkers determination animals.

Language: Английский

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When does early‐life telomere length predict survival? A case study and meta‐analysis

Molecular Ecology, Journal Year: 2023, Volume and Issue: 32(11), P. 3000 - 3013

Published: Feb. 22, 2023

Abstract Suboptimal conditions during development can shorten telomeres, the protective DNA caps on end of chromosomes. Shorter early‐life telomere length (TL) indicate reduced somatic maintenance, leading to lower survival and shorter lifespan. However, despite some clear evidence, not all studies show a relationship between TL or lifespan, which may be due differences in biology study design (e.g., period measured). In superb fairy‐wrens ( Malurus cyaneus ), we assessed whether predicts mortality across different life‐history stages (fledgling, juvenile, adult). contrast similar congener, did predict any life stage this species. We then performed meta‐analysis including 32 effect sizes from 23 (15 birds three mammals) quantify whilst taking into consideration potential sources biological methodological variation. Overall, was significant, corresponding 15% reduction risk with each standard deviation increase TL. became weaker when correcting for publication bias. Contrary our predictions, there no evidence that effects varied species lifespan over measured. negative were pervasive throughout life. These results imply are more likely context‐dependent than age‐dependent, although substantial power bias issues highlight need research.

Language: Английский

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Telomere length declines with age, but relates to immune function independent of age in a wild passerine

Royal Society Open Science, Journal Year: 2022, Volume and Issue: 9(4)

Published: April 1, 2022

Telomere length (TL) shortens with age but telomere dynamics can relate to fitness components independent of age. Immune function often relates such and also interact telomeres. Studying the link between TL immune may therefore help us understand telomere-fitness associations. We assessed relationships erythrocyte four indices (haptoglobin, natural antibodies (NAbs), complement activity (CA) heterophil-lymphocyte (HL) ratio; n = 477-589), from known-aged individuals a wild passerine (Malurus coronatus). As expected, we find that significantly declined To verify whether associations were parallel age-related changes (e.g. immunosenescence), statistically controlled for sampling used within-subject centring separate within or individuals. found positively predicted CA at between-individual level (individuals longer average had higher CA), no other indices. By contrast, levels NAbs HL ratio, allowing inference respective are independent. Any links existing unlikely be strongly mediated by innate function, while appear expressions individual heterogeneity.

Language: Английский

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No effect of testosterone or sexual ornamentation on telomere dynamics: A case study and meta‐analyses

Ecology and Evolution, Journal Year: 2024, Volume and Issue: 14(3)

Published: March 1, 2024

Abstract Life‐history theory predicts that reproductive investments are traded‐off against self‐maintenance. Telomeres, the protective caps on ends of chromosomes, offer a promising avenue for assessing life‐history trade‐offs, as they shorten in response to stressors and predictive remaining lifespan. In males, testosterone frequently mediates part, through its effects sexual ornamentation, which is an important aspect investment. However, studies within‐individual associations between telomere dynamics ornamentation limited number have produced mixed results. Furthermore, most such been observational, making it difficult discern nature any causal relationship. To address this, we used short‐acting implants free‐living male superb fairy‐wrens ( Malurus cyaneus ) stimulate production ornament: early moult into costly blue breeding plumage. We found no evidence elevated testosterone, consequent earlier plumage, accelerated shortening. therefore followed up with systematic review two meta‐analyses (28 studies, 54 effect sizes) exploring telomeres (1) (2) ornamentation. line our experimental findings, neither meta‐analysis showed overall correlation or length dynamics. meta‐regression experimental, compared reported greater trade‐offs. Our highlight need further better understand potential responses

Language: Английский

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Fitness consequences of structural variation inferred from a House Finch pangenome

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: May 17, 2024

Abstract Genomic structural variants (SVs) play a crucial role in adaptive evolution, yet their average fitness effects and characterization with pangenome tools are understudied wild animal populations. We constructed for House Finches, model studies of host-pathogen coevolution, using long-read sequence data on 16 individuals (32 de novo- assembled haplotypes) one outgroup. identified 643,207 SVs larger than 50 base pairs, mostly (60%) involving repetitive elements, reduced SV diversity the eastern US as result its introduction by humans. The distribution genome-wide was estimated maximum likelihood approaches showed both coding non-coding regions to be more deleterious smaller indels or single nucleotide polymorphisms. reference-free facilitated discovery 10-million-year-old, 11-megabase-long pericentric inversion chromosome 1. found that genotype frequencies inversion, from 135 birds widely sampled geographically temporally, increased steadily over 25 years since Finches were first exposed bacterial pathogen Mycoplasma gallispecticum signatures balancing selection, capturing genes related immunity telomerase activity. also observed shorter telomeres populations greater number exposure . Our study illustrates utility applying methods populations, helps estimate SVs, advances our understanding evolution through variation. Significance Statement Prevailing genomic research neutral has focused primarily polymorphisms (SNPs). However, variation (SV) plays critical often directly underlying fitness-relevant traits, although less well understood. constructs Finch sequencing, full spectrum without use reference genome. In addition detecting half million we document large shows evidence contributing disease resistance. sequencing pangenomic bird population presents compelling approach complexities molecular ecology evolution. Graphical abstract

Language: Английский

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Cool, dry nights and short heatwaves during growth result in longer telomeres in temperate songbird nestlings

Molecular Ecology, Journal Year: 2023, Volume and Issue: 32(19), P. 5382 - 5393

Published: Aug. 22, 2023

Abstract Exposure to rising sublethal temperatures can affect development and somatic condition, thereby Darwinian fitness. In the context of climate warming, these changes could have implications for population viability, but they be subtle consequently difficult quantify. Using telomere length (TL) as a known biomarker condition in early life, we investigated impact pre‐hatching nestling on six cohorts wild superb fairy wrens ( Malurus cyaneus ) temperate south‐eastern Australia. Models incorporating only information from phase were best supported compared those including (pre‐)laying incubation (previously shown mass) or both phases combined. This implies that TL is most sensitive ambient phase. The top model showed negative relationship between early‐life mean daily minimum temperature when rainfall was low which gradually became positive with increasing rainfall. addition, there frequency hot days (daily maximum ≥35°C), although rare short‐term. Including other period, variables (e.g., diurnal variability) did not improve prediction TL. Overall, our results suggest cooler nights conditions are dry short‐term spikes above 35°C during conducive maintenance. While findings indicate potential pathway warming wildlife fitness, emphasize need elucidate mechanisms underlying complex associations.

Language: Английский

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No correlative evidence of costs of infection or immunity on leucocyte telomere length in a wild population of Soay sheep

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 291(2020)

Published: April 2, 2024

Telomere length (TL) is a biomarker hypothesized to capture evolutionarily and ecologically important physiological costs of reproduction, infection immunity. Few studies have estimated the relationships among status, immunity, TL fitness in natural systems. The hypothesis that short telomeres predict reduced survival because they reflect costly consequences immune investment remains largely untested. Using longitudinal data from free-living Soay sheep population, we tested whether leucocyte was predicted by with nematode parasites antibody levels against those parasites. Helminth parasite burdens were positively associated both lambs adults, which not consistent reflecting costs. We found no association between helminth-specific IgG either young or old individuals suggests does an activated response immunosenescence. Furthermore, support for acting as mediator trade-offs infection, immunity subsequent wild. Our results suggest while variation could short-term resource environmental conditions, it nor behave like marker individual's response.

Language: Английский

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Shortening of the telomere length during the transition period of dairy cows in relation to biological stress

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: Dec. 30, 2024

Telomere length (TL) is a recognized biomarker for ageing in multiple species. In dairy cattle, the transition period considered very stressful period. We hypothesized that TL shortens during this Holstein cows (n = 61) were followed Blood and milk samples collected at - 7, 3, 6, 9, 21d relative to calving determine concentrations of oxidative, energetic metabolic, inflammatory markers. Average leukocyte was measured by modified qPCR protocol 7d before after parturition. confirmed attrition (P 0.02), as 1.05 ± 0.229 (mean SD) before, 0.97 0.191 Univariable analyses assessed associations between blood markers shortening. Greater plasma oxidative parameters, including oxidized glutathione peroxidase, positively negatively (respectively) associated with attrition. Higher α- β-globulin all associated, while IGF-1, albumin-globulin ratio albumin serum amyloid A haptoglobin linked greater This study reveals significant shortening identifies stress, metabolic inflammation. While these are observed, no causality can be established. Our findings suggest need further research explore effects transition-related stress on dynamics.

Language: Английский

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Senescence in Aging, Within the Brain and Other Diseases: Mechanisms and Interventions

Exploratory Research and Hypothesis in Medicine, Journal Year: 2023, Volume and Issue: 000(000), P. 372 - 387

Published: June 13, 2023

Aging, shifting demographics, and lifestyle changes are some of the underlying factors contributing to an increase in incidence prevalence age-related disorders. Brain health is correlated with cellular senescence important indicator physiological aging several diseases. Examining current state knowledge mechanisms as well prospective therapeutic modalities concerning diseases thus crucial. The senescence-associated secretory phenotype (SASP) senescent cells (SnCs) results a secretome, which primarily composed growth factors, cytokines/chemokines, extracellular matrix (ECM) remodeling proteins secreted by arrested cells. Increasingly, research suggests causative role various such osteoporosis, neurodegenerative diseases, cardiovascular metabolic dysfunction, among others. SnCs promote affecting differentiation proliferation stem They do so, part through disruption Wingless-related integration site (Wnt) signaling pathways Yes-associated protein its ortholog transcriptional coactivators PDZ-binding domain (YAP/TAZ) regulation, tissue regeneration decreased ability for body rejuvenate. Senescent cell-induced immune system dysregulation, e.g., immunosenescence, cell-secreted substances also cause persistent, low-grade inflammation organisms known inflammaging, accelerates damage. During senescence, key chromatin structural take place that affect nuclear transport, causing genomic instability, nucleosome positioning, post-translational modifications histones, global histone loss, etc. Elimination SnCS using senolytics targeting molecular has emerged potential strategy delaying improving dysfunctions including brain

Language: Английский

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