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1.
Z Psychosom Med Psychother ; 69(2): 108-122, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37249378

RESUMEN

Objective: The study aims to assess interrater reliability of the revised Operationalized Psychodynamic Diagnosis 3 (OPD-3) system. Three OPD axes were included in the reliability analysis: the Levels of Structural Integration Axis (OPD-LSIA), the Conflict Axis (OPD-CA), and the Interpersonal Relations Axis (OPD-IRA). Methods: A heterogeneous sample of n = 80 patients was diagnostically assessed with SCID-I and SCID-II as well as with an OPD interview. Two raters of a group of five independently rated each patient's OPD interview according to OPD-3. Results: Interrater reliability was good to excellent for OPD-LSIA [ICC1,1 = .874 - .920], and moderate to good forOPD-CA [ICC1,1 = .547 - .764] as well as forOPD-IRA at the aggregated level of Agency and Communion [ICC1,1 = .575 - .793], except for raters' self-perceived tendencies to act towards the patient. Conclusion: The revised OPD-3 can be used as a reliable instrument for a psychodynamic diagnosis of conflicts, levels of structural integration, and dysfunctional relationship patterns.


Asunto(s)
Terapia Psicoanalítica , Humanos , Reproducibilidad de los Resultados , Relaciones Interpersonales
2.
Proc Natl Acad Sci U S A ; 115(13): 3494-3499, 2018 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-29531040

RESUMEN

Modern European genetic structure demonstrates strong correlations with geography, while genetic analysis of prehistoric humans has indicated at least two major waves of immigration from outside the continent during periods of cultural change. However, population-level genome data that could shed light on the demographic processes occurring during the intervening periods have been absent. Therefore, we generated genomic data from 41 individuals dating mostly to the late 5th/early 6th century AD from present-day Bavaria in southern Germany, including 11 whole genomes (mean depth 5.56×). In addition we developed a capture array to sequence neutral regions spanning a total of 5 Mb and 486 functional polymorphic sites to high depth (mean 72×) in all individuals. Our data indicate that while men generally had ancestry that closely resembles modern northern and central Europeans, women exhibit a very high genetic heterogeneity; this includes signals of genetic ancestry ranging from western Europe to East Asia. Particularly striking are women with artificial skull deformations; the analysis of their collective genetic ancestry suggests an origin in southeastern Europe. In addition, functional variants indicate that they also differed in visible characteristics. This example of female-biased migration indicates that complex demographic processes during the Early Medieval period may have contributed in an unexpected way to shape the modern European genetic landscape. Examination of the panel of functional loci also revealed that many alleles associated with recent positive selection were already at modern-like frequencies in European populations ∼1,500 years ago.


Asunto(s)
Genética de Población , Genoma Humano , Genómica/métodos , Migración Humana , Cráneo/metabolismo , Población Blanca/genética , Arqueología , ADN Antiguo , Femenino , Variación Genética , Alemania , Haplotipos , Historia Medieval , Humanos , Fenotipo , Cráneo/anatomía & histología , Secuenciación Completa del Genoma
3.
Int J Legal Med ; 134(1): 185-198, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31745634

RESUMEN

We present results from an inter-laboratory massively parallel sequencing (MPS) study in the framework of the SeqForSTRs project to evaluate forensically relevant parameters, such as performance, concordance, and sensitivity, using a standardized sequencing library including reference material, mixtures, and ancient DNA samples. The standardized library was prepared using the ForenSeq DNA Signature Prep Kit (primer mix A). The library was shared between eight European laboratories located in Austria, France, Germany, The Netherlands, and Sweden to perform MPS on their particular MiSeq FGx sequencers. Despite variation in performance between sequencing runs, all laboratories obtained quality metrics that fell within the manufacturer's recommended ranges. Furthermore, differences in locus coverage did not inevitably adversely affect heterozygous balance. Inter-laboratory concordance showed 100% concordant genotypes for the included autosomal and Y-STRs, and still, X-STR concordance exceeded 83%. The exclusive reasons for X-STR discordances were drop-outs at DXS10103. Sensitivity experiments demonstrated that correct allele calling varied between sequencing instruments in particular for lower DNA amounts (≤ 125 pg). The analysis of compromised DNA samples showed the drop-out of one sample (FA10013B01A) while for the remaining three degraded DNA samples MPS was able to successfully type ≥ 87% of all aSTRs, ≥ 78% of all Y-STRs, ≥ 68% of all X-STRs, and ≥ 92% of all iSNPs demonstrating that MPS is a promising tool for human identity testing, which in return, has to undergo rigorous in-house validation before it can be implemented into forensic routine casework.


Asunto(s)
Dermatoglifia del ADN/métodos , Biblioteca de Genes , Secuenciación de Nucleótidos de Alto Rendimiento , Repeticiones de Microsatélite , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN , Alelos , Austria , Electroforesis Capilar , Femenino , Francia , Alemania , Humanos , Laboratorios , Masculino , Países Bajos , Reacción en Cadena de la Polimerasa , Sensibilidad y Especificidad , Suecia
4.
Gerontology ; 66(3): 223-230, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32036369

RESUMEN

Across species, development and longevity are tightly linked. We discuss the relevant literature and suggest that the root for this stringent relationship is the rate of development. The basis for the relationship between rate of development and longevity lies in adaptations that have occurred through evolution at multiple levels of biological complexity: organism, organ, cellular, and molecular. Thus, the analysis of the relationship is of interest for multiple fields of biology.


Asunto(s)
Envejecimiento/fisiología , Longevidad/fisiología , Animales , Senescencia Celular/fisiología , Humanos , Telómero/fisiología
5.
Proc Natl Acad Sci U S A ; 113(25): 6886-91, 2016 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-27274049

RESUMEN

Farming and sedentism first appeared in southwestern Asia during the early Holocene and later spread to neighboring regions, including Europe, along multiple dispersal routes. Conspicuous uncertainties remain about the relative roles of migration, cultural diffusion, and admixture with local foragers in the early Neolithization of Europe. Here we present paleogenomic data for five Neolithic individuals from northern Greece and northwestern Turkey spanning the time and region of the earliest spread of farming into Europe. We use a novel approach to recalibrate raw reads and call genotypes from ancient DNA and observe striking genetic similarity both among Aegean early farmers and with those from across Europe. Our study demonstrates a direct genetic link between Mediterranean and Central European early farmers and those of Greece and Anatolia, extending the European Neolithic migratory chain all the way back to southwestern Asia.


Asunto(s)
Agricultura , Antropología , Europa (Continente) , Genética de Población , Humanos , Región Mediterránea , Análisis de Componente Principal
6.
Glia ; 65(3): 431-446, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27888531

RESUMEN

Microglia support productive human immunodeficiency virus type 1 (HIV-1) infection and disturbed microglial function could contribute to the development of HIV-associated neurocognitive disorders (HAND). Better understanding of how HIV-1 infection and viral protein exposure modulate microglial function during the course of infection could lead to the identification of novel therapeutic targets for both the eradication of HIV-1 reservoir and treatment of neurocognitive deficits. This review first describes microglial origins and function in the normal central nervous system (CNS), and the changes that occur during aging. We then critically discuss how HIV-1 infection and exposure to viral proteins such as Tat and gp120 affect various aspects of microglial homeostasis including activation, cellular metabolism and cell cycle regulation, through pathways implicated in cellular stress responses including p38 mitogen-activated protein kinase (MAPK) and nuclear factor κB (NF-κB). We thus propose that the functions of human microglia evolve during both healthy and pathological aging. Aging-associated dysfunction of microglia comprises phenotypes resembling cellular senescence, which could contribute to cognitive impairments observed in various neurodegenerative diseases. In addition, microglia seems to develop characteristics that could be related to cellular senescence post-HIV-1 infection and after exposure to HIV-1 viral proteins. However, despite its potential role as a component of HAND and likely other neurocognitive disorders, microglia senescence has not been well characterized and should be the focus of future studies, which could have high translational relevance. GLIA 2017;65:431-446.


Asunto(s)
Envejecimiento , Infecciones por VIH/patología , Microglía/metabolismo , Microglía/virología , Animales , Humanos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo
7.
Biogerontology ; 18(4): 485-497, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28573417

RESUMEN

In evolutionary terms, life on the planet has taken the form of independently living cells for the majority of time. In comparison, the mammalian radiation is a relatively recent event. The common mammalian ancestor was probably small and short-lived. The "recent" acquisition of an extended longevity and large body mass of some species of mammals present on the earth today suggests the possibility that similar cellular mechanisms have been influenced by the forces of natural selection to create a convergent evolution of longevity. Many cellular mechanisms are potentially relevant for extending longevity; in this assay, we review the literature focusing primarily on two cellular features: (1) the capacity for extensive cellular proliferation of differentiated cells, while maintaining genome stability; and (2) the capacity to detect DNA damage. We have observed that longevity and body mass are both positively linked to these cellular mechanisms and then used statistical tools to evaluate their relative importance. Our analysis suggest that the capacity for extensive cellular proliferation while maintaining sufficient genome stability, correlates to species body mass while the capacity to correctly identify the presence of DNA damage seems more an attribute of long-lived species. Finally, our data are in support of the idea that a slower development, allowing for better DNA damage detection and handling, should associate with longer life span.


Asunto(s)
Evolución Biológica , Tamaño Corporal , Longevidad , Factores de Edad , Envejecimiento/genética , Envejecimiento/metabolismo , Envejecimiento/patología , Animales , Senescencia Celular , Daño del ADN , Metabolismo Energético , Inestabilidad Genómica , Humanos , Modelos Biológicos , Homeostasis del Telómero
8.
Am J Physiol Endocrinol Metab ; 308(7): E545-53, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25648834

RESUMEN

The extension of lifespan due to reduced insulin-like growth factor 1 (IGF-I) signaling in mice has been proposed to be mediated through alterations in metabolism. Previously, we showed that mice homozygous for an insertion in the Igf1 allele have reduced levels of IGF-I, are smaller, and have an extension of maximum lifespan. Here, we tested whether this specific reduction of IGF-I alters glucose metabolism both on normal rodent chow and in response to high-fat feeding. We found that female IGF-I-deficient mice were lean on a standard rodent diet but paradoxically displayed an insulin-resistant phenotype. However, these mice gained significantly less weight than normal controls when placed on a high-fat diet. In control animals, insulin response was significantly impaired by high-fat feeding, whereas IGF-I-deficient mice showed a much smaller shift in insulin response after high-fat feeding. Gluconeogenesis was also elevated in the IGF-I-deficient mice relative to controls on both normal and high-fat diet. An analysis of metabolism and respiratory quotient over 24 h indicated that the IGF-I-deficient mice preferentially utilized fatty acids as an energy source when placed on a high-fat diet. These results indicate that reduction in the circulating and tissue IGF-I levels can produce a metabolic phenotype in female mice that increases peripheral insulin resistance but renders animals resistant to the deleterious effects of high-fat feeding.


Asunto(s)
Resistencia a la Enfermedad , Metabolismo Energético/genética , Factor I del Crecimiento Similar a la Insulina/genética , Longevidad , Obesidad/genética , Animales , Composición Corporal/genética , Dieta Alta en Grasa , Resistencia a la Enfermedad/genética , Femenino , Resistencia a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Longevidad/genética , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Obesidad/metabolismo
9.
Front Psychol ; 14: 1152150, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37151325

RESUMEN

Personality functioning and psychodynamic conflicts are central constructs in psychoanalytic theories of psychopathology as well as in many psychodynamic treatment models. Although there has been a longstanding conceptual discussion on how they relate to each other, empirical evidence on this question is still scarce. In this study, we explore the associations between psychodynamic conflicts and levels of structural integration (which can be used synonymously with personality functioning) by means of a partial correlation network analysis in a sample of N = 220 outpatients interviewed and rated according to Operationalized Psychodynamic Diagnosis (OPD-2). We examined network centrality, bridge centrality, clustering, and network stability. The network analysis resulted in separate clusters for levels of structural integration and conflicts, supporting the assumption of distinct psychodynamic constructs. The greatest association between the two clusters was found between the individuation vs. dependency conflict (C1) and the structural capacity to attach to internal objects. In general, C1 showed significantly greater connections with structural dimensions compared to the other five OPD conflicts included. C1 was also more central in the network compared to most other conflicts, whereas the structural dimensions did not differ in centrality. All structural dimensions were found to be strongly interconnected. C1 showed exclusively negative edges to the other conflicts, suggesting that a profound C1 decreases the probability of other psychodynamic conflicts. We discuss clinical as well as conceptual implications of our findings for psychodynamic diagnosis and treatment.

10.
Biomed J ; 46(3): 100596, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37149260

RESUMEN

BACKGROUND: The Peto's paradox consists in the observation that individuals from long-lived and large animal species do not experience a higher cancer incidence, despite being exposed for longer time to the possibility of accumulating mutations and having more target cells exposed to the phenomenon. The existence of this paradox has been recently confirmed (Vincze et al., 2022). Concurrently, robust evidence has been published that longevity involves a convergent evolution of cellular mechanisms that prevent the accumulation of mutations (Cagan et al., 2022). It remains unclear which cellular mechanisms are critical to allow the evolution of a large body mass while keeping cancer at bay. METHODS: Adding to existing data linking cellular replicative potential and species body mass (Lorenzini et al., 2005), we have grown a total of 84 skin fibroblast cell strains from 40 donors of 17 mammalian species and analyzed their Hayflick's limit, i.e., their senescent plateau, and eventual spontaneous immortalization escape. The correlation of immortalization and replicative capacity of the species with their longevity, body mass and metabolism has been assessed through phylogenetic multiple linear regression (MLR). RESULTS: The immortalization probability is negatively related to species body mass. The new evaluation and additional data about replicative potential strengthen our previous observation, confirming that stable and extended proliferation is strongly correlated with the evolution of a large body mass rather than lifespan. CONCLUSION: The relation between immortalization and body mass suggests a need to evolve stringent mechanisms that control genetic stability during the evolution of a large body mass.


Asunto(s)
Longevidad , Neoplasias , Animales , Filogenia , Técnicas de Cultivo de Célula , Probabilidad , Mamíferos
11.
Biomed J ; 47(2): 100654, 2023 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-37604250

RESUMEN

Comparative oncology is an understudied field of science. We are far from understanding the key mechanisms behind Peto's paradox, i.e., understanding how long-lived and large animals are not subject to a higher cancer burden despite the longer exposure time to mutations and the larger number of cells exposed. In this work, we investigated the scientific evidence on such mechanisms through a systematic mini-review of the literature about the relation of longevity and/or large body mass with physiological, genetic, or environmental traits among mammalian species. More than forty thousand articles were retrieved from three repositories, and 383 of them were screened using an active-learning-based tool. Of those, 36 articles on longevity and 37 on body mass were selected for the review. Such articles were examined focusing on: number and type of species considered, statistical methods used, traits investigated, and observed relationship with longevity and/or body mass. Where applicable, the traits investigated were matched with one or more hallmarks of cancer. We obtained a list of potential candidate traits to explain Peto's paradox related to replicative immortality, cell senescence, genome instability and mutations, proliferative signaling, growth suppression evasion, and cell resistance to death. Our investigation suggests that different strategies have been followed to prevent cancer in large and long-lived species. The large number of papers retrieved emphasizes that more studies can be launched in the future, using more efficient analytical approaches to comprehensively evaluate the convergent biological mechanisms essential for acquiring longevity and large body mass without increasing cancer risk.

12.
Geroscience ; 44(2): 683-698, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34550526

RESUMEN

Persistent DNA damage (genotoxic stress) triggers signaling cascades that drive cells into apoptosis or senescence to avoid replicating a damaged genome. Sp1 has been found to play a role in double strand break (DSB) repair, and a link between Sp1 and aging has also been established, where Sp1 protein, but not RNA, levels decrease with age. Interestingly, inhibition ATM reverses the age-related degradation of Sp1, suggesting that DNA damage signaling is involved in senescence-related degradation of Sp1. Proteasomal degradation of Sp1 in senescent cells is mediated via sumoylation, where sumoylation of Sp1 on lysine 16 is increased in senescent cells. Taking into consideration our previous findings that Sp1 is phosphorylated by ATM in response to DNA damage and that proteasomal degradation of Sp1 at DSBs is also mediated by its sumoylation and subsequent interaction with RNF4, we investigated the potential contribution of Sp1's role as a DSB repair factor in mediating cellular senescence. We report here that Sp1 expression is decreased with a concomitant increase in senescence markers in response to DNA damage. Mutation of Sp1 at serine 101 to create an ATM phospho-null mutant, or mutation of lysine 16 to create a sumo-null mutant, prevents the sumoylation and subsequent proteasomal degradation of Sp1 and results in a decrease in senescence. Conversely, depletion of Sp1 or mutation of Sp1 to create an ATM phosphomimetic results in premature degradation of Sp1 and an increase in senescence markers. These data link a loss of genomic stability with senescence through the action of a DNA damage repair factor.


Asunto(s)
Daño del ADN , Lisina , Senescencia Celular , Reparación del ADN , Sumoilación
13.
Mol Biol Cell ; 33(5): ar36, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35196069

RESUMEN

Cellular senescence is a terminal cell fate characterized by growth arrest and a metabolically active state characterized by high glycolytic activity. Human fibroblasts were placed in a unique metabolic state using a combination of methionine restriction (MetR) and rapamycin (Rapa). This combination induced a metabolic reprogramming that prevented the glycolytic shift associated with senescence. Surprisingly, cells treated in this manner did not undergo senescence but continued to divide at a slow rate even at high passage, in contrast with either Rapa treatment or MetR, both of which extended life span but eventually resulted in growth arrest. Transcriptome-wide analysis revealed a coordinated regulation of metabolic enzymes related to one-carbon metabolism including three methyltransferase enzymes (KMT2D, SETD1B, and ASH1L), key enzymes for both carnitine synthesis and histone modification. These enzymes appear to be involved in both the metabolic phenotype of senescent cells and the chromatin changes required for establishing the senescence arrest. Targeting one of these enzymes, ASH1L, produced both a glycolytic shift and senescence, providing proof of concept. These findings reveal a mechanistic link between a major metabolic hallmark of senescence and nuclear events required for senescence.


Asunto(s)
Senescencia Celular , Epigénesis Genética , Senescencia Celular/genética , Fibroblastos/metabolismo , Glucólisis , Metionina/metabolismo , Sirolimus/farmacología
14.
Exp Cell Res ; 316(17): 2961-8, 2010 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-20620137

RESUMEN

There is an increasing awareness that astrocytes, the most abundant cell type in the central nervous system, are critical mediators of brain homeostasis, playing multifunctional roles including buffering potassium ions, maintaining the blood-brain barrier, releasing growth factors, and regulating neurotransmitter levels. Defects in astrocyte function have been implicated in a variety of diseases including age-related diseases such Alzheimer's disease and Parkinson's disease. However, little is known about the age-related changes that occur in astrocytes and if these cells are able to generate a senescent phenotype in response to stress. In this report we have examined whether astrocytes can initiate a senescence program similar to that described in other cell types in response to a variety of stresses. Our results indicate that after oxidative stress, proteasome inhibition, or exhausted replication, human and mouse astrocytes show changes in several established markers of cellular senescence. Astrocytes appear to be more sensitive to oxidative stress than fibroblasts, suggesting that stress-induced senescence may be more pronounced in the brain than in other tissues.


Asunto(s)
Astrocitos/citología , Senescencia Celular , Estrés Fisiológico/fisiología , Animales , Células Cultivadas , Fibroblastos/citología , Humanos , Ratones , Estrés Oxidativo/fisiología , Inhibidores de Proteasoma
15.
Res Psychother ; 24(3): 577, 2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-35047430

RESUMEN

Guided imagery psychotherapy (GIP) is an established therapeutic method using creative mental imagery within a psychodynamic frame of reference. Although there is evidence for the method's general effectiveness, it is yet unclear under which conditions and for which patients it should be used. The aim of this study was therefore to empirically identify indication criteria for the use of guided affective imagery (GAI) as part of psychodynamic therapies. We conducted semi-structured interviews with N=15 psychodynamic therapists also qualified as GAI training therapists. We asked them to recollect cases in which they had decided either for or against the use of imagery. The therapists described a complex interplay of different factors. Using grounded theory coding supplemented by elements of Consensual Qualitative Research we reconstructed from their accounts a sequential model of their indicative decisions. First, there is a consideration of clear contraindications related to reality testing and destructiveness. Second, there are aspects requiring a modified application of GAI such as emotional instability and post-traumatic stress disorder symptoms. In a final step, there are a number of characteristics of the patient, the therapist, the therapeutic relationship, the patients' initial imagery and different therapeutic goals and foci which are weighed relatively to each other in order for therapists to reach an indication decision. We end by discussing ways in which the indicative decision model may be used to improve GAI training as well as the method's differential efficacy and effectiveness.

16.
Cell Cycle ; 20(3): 247-255, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33475456

RESUMEN

A key to longevity assurance is the nutrient-sensing mTOR pathway. Inhibition of mTOR extends lifespan in a variety of organisms. However, the downstream effectors of the mTOR pathway for lifespan regulation are elusive. In a recent report, we described the role of Maf1 as a critical lifespan regulator downstream of the mTOR pathway in fission yeast. Maf1 is the master negative regulator of RNA polymerase III-directed transcription (e.g. tRNAs and 5S rRNAs) and is regulated by mTOR-mediated phosphorylation. We demonstrated that Maf1 is required for lifespan extension under calorie restriction or when mTOR is inhibited. We also showed that Maf1 prevents DNA damage at tRNA genes, which appears to contribute to lifespan maintenance by Maf1. Here we highlight these observations and present additional results to discuss the role of the mTOR-Maf1-Pol III axis in promoting genomic integrity in the face of DNA replication-transcription conflicts in order to maintain normal lifespan.


Asunto(s)
Daño del ADN/fisiología , Longevidad/fisiología , ARN Polimerasa III/genética , Proteínas Represoras/genética , Proteínas de Schizosaccharomyces pombe/genética , Serina-Treonina Quinasas TOR/genética , Transcripción Genética/fisiología , Restricción Calórica/métodos , ARN Polimerasa III/metabolismo , Proteínas Represoras/metabolismo , Schizosaccharomyces , Proteínas de Schizosaccharomyces pombe/metabolismo , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/metabolismo
17.
Geroscience ; 42(2): 813-815, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32227278

RESUMEN

A response is provided to a commentary on a recent study examining the impact of low-dose topical application of rapamycin on markers of aging in the skin. The barriers to clinical implementation of therapies targeting the fundamental aging process are discussed, and the topical study is placed in context with the broader effort to develop new therapeutics for age-related disorders.


Asunto(s)
Sirolimus , Envejecimiento de la Piel , Envejecimiento , Humanos , Inmunosupresores , Estudios Prospectivos
18.
Geroscience ; 42(3): 867-879, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31098949

RESUMEN

Cellular senescence is a fundamental process that may play positive or detrimental roles for the organism. It is involved in tissue development and in tumor prevention although during aging is becoming a detrimental process contributing to the decline of tissue functions. In previous investigations, we have uncovered a better capacity to detect DNA damage in cells from long-lived mammals. Here, we report that cultured cells derived from long-lived species have a higher propensity to undergo senescence when challenged with DNA damage than cells derived from short-lived species. Using a panel of cells derived from six mammals, which range in lifespan from 3-4 years up to 120 years, we examined cell cycle response, induction of apoptosis and of cellular senescence. All species exhibited a cell cycle arrest while induction of apoptosis was variable. However, a significant positive correlation was found between the relative percent of cells, within a population which entered senescence following damage, and the lifespan of the species. We suggest that cellular senescence may have a positive role during development allowing it to contribute to the evolution of longevity.


Asunto(s)
Senescencia Celular , Longevidad , Envejecimiento , Animales , Daño del ADN , beta-Galactosidasa
19.
Aging Cell ; 19(2): e13068, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31833215

RESUMEN

Maf1 is the master repressor of RNA polymerase III responsible for transcription of tRNAs and 5S rRNAs. Maf1 is negatively regulated via phosphorylation by the mTOR pathway, which governs protein synthesis, growth control, and lifespan regulation in response to nutrient availability. Inhibiting the mTOR pathway extends lifespan in various organisms. However, the downstream effectors for the regulation of cell homeostasis that are critical to lifespan extension remain elusive. Here we show that fission yeast Maf1 is required for lifespan extension. Maf1's function in tRNA repression is inhibited by mTOR-dependent phosphorylation, whereas Maf1 is activated via dephosphorylation by protein phosphatase complexes, PP4 and PP2A. Mutational analysis reveals that Maf1 phosphorylation status influences lifespan, which is correlated with elevated tRNA and protein synthesis levels in maf1∆ cells. However, mTOR downregulation, which negates protein synthesis, fails to rescue the short lifespan of maf1∆ cells, suggesting that elevated protein synthesis is not a cause of lifespan shortening in maf1∆ cells. Interestingly, maf1∆ cells accumulate DNA damage represented by formation of Rad52 DNA damage foci and Rad52 recruitment at tRNA genes. Loss of the Rad52 DNA repair protein further exacerbates the shortened lifespan of maf1∆ cells. Strikingly, PP4 deletion alleviates DNA damage and rescues the short lifespan of maf1∆ cells even though tRNA synthesis is increased in this condition, suggesting that elevated DNA damage is the major cause of lifespan shortening in maf1∆ cells. We propose that Maf1-dependent inhibition of tRNA synthesis controls fission yeast lifespan by preventing genomic instability that arises at tRNA genes.


Asunto(s)
Regulación Fúngica de la Expresión Génica , Inestabilidad Genómica/genética , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , ARN de Transferencia/genética , Proteínas Represoras/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/genética , Inmunoprecipitación de Cromatina , Daño del ADN/genética , Glucosa/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Fosfoproteínas Fosfatasas/genética , Fosfoproteínas Fosfatasas/metabolismo , Fosforilación , Biosíntesis de Proteínas/genética , Biosíntesis de Proteínas/fisiología , Proteína Fosfatasa 2/genética , Proteína Fosfatasa 2/metabolismo , ARN de Transferencia/biosíntesis , ARN de Transferencia/metabolismo , Proteína Recombinante y Reparadora de ADN Rad52/genética , Proteína Recombinante y Reparadora de ADN Rad52/metabolismo , Proteínas Represoras/genética , Schizosaccharomyces/metabolismo , Schizosaccharomyces/fisiología , Proteínas de Schizosaccharomyces pombe/genética
20.
Curr Biol ; 30(21): 4307-4315.e13, 2020 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-32888485

RESUMEN

Lactase persistence (LP), the continued expression of lactase into adulthood, is the most strongly selected single gene trait over the last 10,000 years in multiple human populations. It has been posited that the primary allele causing LP among Eurasians, rs4988235-A [1], only rose to appreciable frequencies during the Bronze and Iron Ages [2, 3], long after humans started consuming milk from domesticated animals. This rapid rise has been attributed to an influx of people from the Pontic-Caspian steppe that began around 5,000 years ago [4, 5]. We investigate the spatiotemporal spread of LP through an analysis of 14 warriors from the Tollense Bronze Age battlefield in northern Germany (∼3,200 before present, BP), the oldest large-scale conflict site north of the Alps. Genetic data indicate that these individuals represent a single unstructured Central/Northern European population. We complemented these data with genotypes of 18 individuals from the Bronze Age site Mokrin in Serbia (∼4,100 to ∼3,700 BP) and 37 individuals from Eastern Europe and the Pontic-Caspian Steppe region, predating both Bronze Age sites (∼5,980 to ∼3,980 BP). We infer low LP in all three regions, i.e., in northern Germany and South-eastern and Eastern Europe, suggesting that the surge of rs4988235 in Central and Northern Europe was unlikely caused by Steppe expansions. We estimate a selection coefficient of 0.06 and conclude that the selection was ongoing in various parts of Europe over the last 3,000 years.


Asunto(s)
ADN Antiguo , Lactasa/genética , Selección Genética , Población Blanca/genética , Adulto , Restos Mortales , ADN Mitocondrial/genética , Europa (Continente) , Femenino , Frecuencia de los Genes , Humanos , Masculino , Adulto Joven
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