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1.
Cell ; 187(10): 2465-2484.e22, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38701782

RESUMO

Remyelination failure in diseases like multiple sclerosis (MS) was thought to involve suppressed maturation of oligodendrocyte precursors; however, oligodendrocytes are present in MS lesions yet lack myelin production. We found that oligodendrocytes in the lesions are epigenetically silenced. Developing a transgenic reporter labeling differentiated oligodendrocytes for phenotypic screening, we identified a small-molecule epigenetic-silencing-inhibitor (ESI1) that enhances myelin production and ensheathment. ESI1 promotes remyelination in animal models of demyelination and enables de novo myelinogenesis on regenerated CNS axons. ESI1 treatment lengthened myelin sheaths in human iPSC-derived organoids and augmented (re)myelination in aged mice while reversing age-related cognitive decline. Multi-omics revealed that ESI1 induces an active chromatin landscape that activates myelinogenic pathways and reprograms metabolism. Notably, ESI1 triggered nuclear condensate formation of master lipid-metabolic regulators SREBP1/2, concentrating transcriptional co-activators to drive lipid/cholesterol biosynthesis. Our study highlights the potential of targeting epigenetic silencing to enable CNS myelin regeneration in demyelinating diseases and aging.


Assuntos
Epigênese Genética , Bainha de Mielina , Oligodendroglia , Remielinização , Animais , Bainha de Mielina/metabolismo , Humanos , Camundongos , Remielinização/efeitos dos fármacos , Oligodendroglia/metabolismo , Sistema Nervoso Central/metabolismo , Camundongos Endogâmicos C57BL , Rejuvenescimento , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Organoides/metabolismo , Organoides/efeitos dos fármacos , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/genética , Diferenciação Celular/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Masculino , Regeneração/efeitos dos fármacos , Esclerose Múltipla/metabolismo , Esclerose Múltipla/genética , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/patologia
2.
Nat Rev Mol Cell Biol ; 24(1): 45-62, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35859206

RESUMO

Most adult organs contain regenerative stem cells, often organized in specific niches. Stem cell function is critical for tissue homeostasis and repair upon injury, and it is dependent on interactions with the niche. During ageing, stem cells decline in their regenerative potential and ability to give rise to differentiated cells in the tissue, which is associated with a deterioration of tissue integrity and health. Ageing-associated changes in regenerative tissue regions include defects in maintenance of stem cell quiescence, differentiation ability and bias, clonal expansion and infiltration of immune cells in the niche. In this Review, we discuss cellular and molecular mechanisms underlying ageing in the regenerative regions of different tissues as well as potential rejuvenation strategies. We focus primarily on brain, muscle and blood tissues, but also provide examples from other tissues, such as skin and intestine. We describe the complex interactions between different cell types, non-cell-autonomous mechanisms between ageing niches and stem cells, and the influence of systemic factors. We also compare different interventions for the rejuvenation of old regenerative regions. Future outlooks in the field of stem cell ageing are discussed, including strategies to counter ageing and age-dependent disease.


Assuntos
Rejuvenescimento , Células-Tronco , Senescência Celular/fisiologia , Diferenciação Celular , Nicho de Células-Tronco
3.
Nat Rev Mol Cell Biol ; 21(3): 137-150, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32020082

RESUMO

Ageing is characterized by the functional decline of tissues and organs and the increased risk of ageing-associated disorders. Several 'rejuvenating' interventions have been proposed to delay ageing and the onset of age-associated decline and disease to extend healthspan and lifespan. These interventions include metabolic manipulation, partial reprogramming, heterochronic parabiosis, pharmaceutical administration and senescent cell ablation. As the ageing process is associated with altered epigenetic mechanisms of gene regulation, such as DNA methylation, histone modification and chromatin remodelling, and non-coding RNAs, the manipulation of these mechanisms is central to the effectiveness of age-delaying interventions. This Review discusses the epigenetic changes that occur during ageing and the rapidly increasing knowledge of how these epigenetic mechanisms have an effect on healthspan and lifespan extension, and outlines questions to guide future research on interventions to rejuvenate the epigenome and delay ageing processes.


Assuntos
Envelhecimento/genética , Epigênese Genética/genética , Rejuvenescimento/fisiologia , Animais , Montagem e Desmontagem da Cromatina/genética , Metilação de DNA/genética , Epigenoma/genética , Epigenômica/métodos , Regulação da Expressão Gênica/genética , Código das Histonas/genética , Humanos , Longevidade/genética
4.
Cell ; 169(1): 3-5, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-28340347

RESUMO

In this issue of Cell, Baar et al. show how FOXO4 protects senescent cell viability by keeping p53 sequestered in nuclear bodies, preventing it from inducing apoptosis. Disrupting this interaction with an all-D amino acid peptide (FOXO4-DRI) restores p53's apoptotic role and ameliorates the consequences of senescence-associated loss of tissue homeostasis.


Assuntos
Apoptose , Rejuvenescimento , Sobrevivência Celular , Senescência Celular , Humanos , Proteína Supressora de Tumor p53/química
5.
Genes Dev ; 38(17-20): 823-842, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39293862

RESUMO

Cellular plasticity in adult multicellular organisms is a protective mechanism that allows certain tissues to regenerate in response to injury. Considering that aging involves exposure to repeated injuries over a lifetime, it is conceivable that cell identity itself is more malleable-and potentially erroneous-with age. In this review, we summarize and critically discuss the available evidence that cells undergo age-related shifts in identity, with an emphasis on those that contribute to age-associated pathologies, including neurodegeneration and cancer. Specifically, we focus on reported instances of programs associated with dedifferentiation, biased differentiation, acquisition of features from alternative lineages, and entry into a preneoplastic state. As some of the most promising approaches to rejuvenate cells reportedly also elicit transient changes to cell identity, we further discuss whether cell state change and rejuvenation can be uncoupled to yield more tractable therapeutic strategies.


Assuntos
Envelhecimento , Plasticidade Celular , Rejuvenescimento , Humanos , Envelhecimento/fisiologia , Animais , Rejuvenescimento/fisiologia , Diferenciação Celular , Senescência Celular/fisiologia
7.
Annu Rev Genet ; 56: 89-112, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-35878627

RESUMO

Gametogenesis is a conserved developmental program whereby a diploid progenitor cell differentiates into haploid gametes, the precursors for sexually reproducing organisms. In addition to ploidy reduction and extensive organelle remodeling, gametogenesis naturally rejuvenates the ensuing gametes, leading to resetting of life span. Excitingly, ectopic expression of the gametogenesis-specific transcription factor Ndt80 is sufficient to extend life span in mitotically dividing budding yeast, suggesting that meiotic rejuvenation pathways can be repurposed outside of their natural context. In this review, we highlight recent studies of gametogenesis that provide emerging insight into natural quality control, organelle remodeling, and rejuvenation strategies that exist within a cell. These include selective inheritance, programmed degradation, and de novo synthesis, all of which are governed by the meiotic gene expression program entailing many forms of noncanonical gene regulation. Finally, we highlight critical questions that remain in the field and provide perspective on the implications of gametogenesis research on human health span.


Assuntos
Gametogênese , Rejuvenescimento , Humanos , Gametogênese/genética , Senescência Celular , Controle de Qualidade , Haploidia
8.
Nature ; 628(8006): 162-170, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38538791

RESUMO

Ageing of the immune system is characterized by decreased lymphopoiesis and adaptive immunity, and increased inflammation and myeloid pathologies1,2. Age-related changes in populations of self-renewing haematopoietic stem cells (HSCs) are thought to underlie these phenomena3. During youth, HSCs with balanced output of lymphoid and myeloid cells (bal-HSCs) predominate over HSCs with myeloid-biased output (my-HSCs), thereby promoting the lymphopoiesis required for initiating adaptive immune responses, while limiting the production of myeloid cells, which can be pro-inflammatory4. Ageing is associated with increased proportions of my-HSCs, resulting in decreased lymphopoiesis and increased myelopoiesis3,5,6. Transfer of bal-HSCs results in abundant lymphoid and myeloid cells, a stable phenotype that is retained after secondary transfer; my-HSCs also retain their patterns of production after secondary transfer5. The origin and potential interconversion of these two subsets is still unclear. If they are separate subsets postnatally, it might be possible to reverse the ageing phenotype by eliminating my-HSCs in aged mice. Here we demonstrate that antibody-mediated depletion of my-HSCs in aged mice restores characteristic features of a more youthful immune system, including increasing common lymphocyte progenitors, naive T cells and B cells, while decreasing age-related markers of immune decline. Depletion of my-HSCs in aged mice improves primary and secondary adaptive immune responses to viral infection. These findings may have relevance to the understanding and intervention of diseases exacerbated or caused by dominance of the haematopoietic system by my-HSCs.


Assuntos
Imunidade Adaptativa , Envelhecimento , Linhagem da Célula , Células-Tronco Hematopoéticas , Linfócitos , Células Mieloides , Rejuvenescimento , Animais , Feminino , Masculino , Camundongos , Imunidade Adaptativa/imunologia , Envelhecimento/imunologia , Linfócitos B/citologia , Linfócitos B/imunologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/imunologia , Inflamação/imunologia , Inflamação/patologia , Linfócitos/citologia , Linfócitos/imunologia , Linfopoese , Células Mieloides/citologia , Células Mieloides/imunologia , Mielopoese , Fenótipo , Linfócitos T/citologia , Linfócitos T/imunologia , Vírus/imunologia
9.
Genes Dev ; 36(1-2): 23-37, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34916302

RESUMO

The regenerative potential of neural stem cells (NSCs) declines during aging, leading to cognitive dysfunctions. This decline involves up-regulation of senescence-associated genes, but inactivation of such genes failed to reverse aging of hippocampal NSCs. Because many genes are up-regulated or down-regulated during aging, manipulation of single genes would be insufficient to reverse aging. Here we searched for a gene combination that can rejuvenate NSCs in the aged mouse brain from nuclear factors differentially expressed between embryonic and adult NSCs and their modulators. We found that a combination of inducing the zinc finger transcription factor gene Plagl2 and inhibiting Dyrk1a, a gene associated with Down syndrome (a genetic disorder known to accelerate aging), rejuvenated aged hippocampal NSCs, which already lost proliferative and neurogenic potential. Such rejuvenated NSCs proliferated and produced new neurons continuously at the level observed in juvenile hippocampi, leading to improved cognition. Epigenome, transcriptome, and live-imaging analyses indicated that this gene combination induces up-regulation of embryo-associated genes and down-regulation of age-associated genes by changing their chromatin accessibility, thereby rejuvenating aged dormant NSCs to function like juvenile active NSCs. Thus, aging of NSCs can be reversed to induce functional neurogenesis continuously, offering a way to treat age-related neurological disorders.


Assuntos
Células-Tronco Neurais , Rejuvenescimento , Animais , Hipocampo , Camundongos , Neurogênese/genética , Neurônios
10.
Nature ; 621(7977): 196-205, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37612507

RESUMO

Abundant high-molecular-mass hyaluronic acid (HMM-HA) contributes to cancer resistance and possibly to the longevity of the longest-lived rodent-the naked mole-rat1,2. To study whether the benefits of HMM-HA could be transferred to other animal species, we generated a transgenic mouse overexpressing naked mole-rat hyaluronic acid synthase 2 gene (nmrHas2). nmrHas2 mice showed an increase in hyaluronan levels in several tissues, and a lower incidence of spontaneous and induced cancer, extended lifespan and improved healthspan. The transcriptome signature of nmrHas2 mice shifted towards that of longer-lived species. The most notable change observed in nmrHas2 mice was attenuated inflammation across multiple tissues. HMM-HA reduced inflammation through several pathways, including a direct immunoregulatory effect on immune cells, protection from oxidative stress and improved gut barrier function during ageing. These beneficial effects were conferred by HMM-HA and were not specific to the nmrHas2 gene. These findings demonstrate that the longevity mechanism that evolved in the naked mole-rat can be exported to other species, and open new paths for using HMM-HA to improve lifespan and healthspan.


Assuntos
Envelhecimento Saudável , Hialuronan Sintases , Ácido Hialurônico , Longevidade , Ratos-Toupeira , Animais , Camundongos , Ácido Hialurônico/biossíntese , Ácido Hialurônico/metabolismo , Inflamação/genética , Inflamação/imunologia , Inflamação/prevenção & controle , Camundongos Transgênicos , Ratos-Toupeira/genética , Longevidade/genética , Longevidade/imunologia , Longevidade/fisiologia , Hialuronan Sintases/genética , Hialuronan Sintases/metabolismo , Envelhecimento Saudável/genética , Envelhecimento Saudável/imunologia , Envelhecimento Saudável/fisiologia , Transgenes/genética , Transgenes/fisiologia , Transcriptoma , Neoplasias/genética , Neoplasias/prevenção & controle , Estresse Oxidativo , Gerociência , Rejuvenescimento/fisiologia
11.
EMBO J ; 43(16): 3312-3326, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39009672

RESUMO

Aging is associated with a progressive decline of brain function, and the underlying causes and possible interventions to prevent this cognitive decline have been the focus of intense investigation. The maintenance of neuronal function over the lifespan requires proper epigenetic regulation, and accumulating evidence suggests that the deterioration of the neuronal epigenetic landscape contributes to brain dysfunction during aging. Epigenetic aging of neurons may, however, be malleable. Recent reports have shown age-related epigenetic changes in neurons to be reversible and targetable by rejuvenation strategies that can restore brain function during aging. This review discusses the current evidence that identifies neuronal epigenetic aging as a driver of cognitive decline and a promising target of brain rejuvenation strategies, and it highlights potential approaches for the specific manipulation of the aging neuronal epigenome to restore a youthful epigenetic state in the brain.


Assuntos
Envelhecimento , Encéfalo , Epigênese Genética , Epigenoma , Neurônios , Humanos , Encéfalo/metabolismo , Animais , Neurônios/metabolismo , Envelhecimento/genética , Rejuvenescimento/fisiologia , Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo
12.
Nature ; 603(7900): 309-314, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35236985

RESUMO

The ability to slow or reverse biological ageing would have major implications for mitigating disease risk and maintaining vitality1. Although an increasing number of interventions show promise for rejuvenation2, their effectiveness on disparate cell types across the body and the molecular pathways susceptible to rejuvenation remain largely unexplored. Here we performed single-cell RNA sequencing on 20 organs to reveal cell-type-specific responses to young and aged blood in heterochronic parabiosis. Adipose mesenchymal stromal cells, haematopoietic stem cells and hepatocytes are among those cell types that are especially responsive. On the pathway level, young blood invokes new gene sets in addition to reversing established ageing patterns, with the global rescue of genes encoding electron transport chain subunits pinpointing a prominent role of mitochondrial function in parabiosis-mediated rejuvenation. We observed an almost universal loss of gene expression with age that is largely mimicked by parabiosis: aged blood reduces global gene expression, and young blood restores it in select cell types. Together, these data lay the groundwork for a systemic understanding of the interplay between blood-borne factors and cellular integrity.


Assuntos
Parabiose , Análise de Célula Única , Adipócitos , Envelhecimento/genética , Transporte de Elétrons/genética , Células-Tronco Hematopoéticas , Hepatócitos , Células-Tronco Mesenquimais , Mitocôndrias , Especificidade de Órgãos/genética , RNA-Seq , Rejuvenescimento
13.
Nature ; 611(7935): 358-364, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36323784

RESUMO

The accumulation of senescent cells is a major cause of age-related inflammation and predisposes to a variety of age-related diseases1. However, little is known about the molecular basis underlying this accumulation and its potential as a target to ameliorate the ageing process. Here we show that senescent cells heterogeneously express the immune checkpoint protein programmed death-ligand 1 (PD-L1) and that PD-L1+ senescent cells accumulate with age in vivo. PD-L1- cells are sensitive to T cell surveillance, whereas PD-L1+ cells are resistant, even in the presence of senescence-associated secretory phenotypes (SASP). Single-cell analysis of p16+ cells in vivo revealed that PD-L1 expression correlated with higher levels of SASP. Consistent with this, administration of programmed cell death protein 1 (PD-1) antibody to naturally ageing mice or a mouse model with normal livers or induced nonalcoholic steatohepatitis reduces the total number of p16+ cells in vivo as well as the PD-L1+ population in an activated CD8+ T cell-dependent manner, ameliorating various ageing-related phenotypes. These results suggest that the heterogeneous expression of PD-L1 has an important role in the accumulation of senescent cells and inflammation associated with ageing, and the elimination of PD-L1+ senescent cells by immune checkpoint blockade may be a promising strategy for anti-ageing therapy.


Assuntos
Envelhecimento , Antígeno B7-H1 , Fenótipo , Receptor de Morte Celular Programada 1 , Animais , Camundongos , Envelhecimento/imunologia , Envelhecimento/metabolismo , Envelhecimento/patologia , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Inflamação/patologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/metabolismo , Análise de Célula Única , Hepatopatia Gordurosa não Alcoólica , Fígado , Rejuvenescimento
14.
Development ; 151(20)2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39399899

RESUMO

Meiosis is a hallmark of sexual reproduction because it represents the transition from one life cycle to the next and, in animals, meiosis produces gametes. Why meiosis evolved has been debated and most studies have focused on recombination of the parental alleles as the main function of meiosis. However, 40 years ago, Robin Holliday proposed that an essential function of meiosis is to oppose the consequence of successive mitoses that cause cellular aging. Cellular aging results from accumulated defective organelles and proteins and modifications of chromatin in the form of DNA methylation and histone modifications referred to collectively as epigenetic marks. Here, recent findings supporting the hypothesis that meiosis opposes cellular aging are reviewed and placed in the context of the diversity of the life cycles of eukaryotes, including animals, yeast, flowering plants and the bryophyte Marchantia.


Assuntos
Epigênese Genética , Meiose , Meiose/genética , Animais , Humanos , Reprogramação Celular/genética , Senescência Celular/genética , Metilação de DNA/genética , Rejuvenescimento/fisiologia
15.
Cell ; 148(1-2): 46-57, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22265401

RESUMO

The underlying cause of aging remains one of the central mysteries of biology. Recent studies in several different systems suggest that not only may the rate of aging be modified by environmental and genetic factors, but also that the aging clock can be reversed, restoring characteristics of youthfulness to aged cells and tissues. This Review focuses on the emerging biology of rejuvenation through the lens of epigenetic reprogramming. By defining youthfulness and senescence as epigenetic states, a framework for asking new questions about the aging process emerges.


Assuntos
Envelhecimento/genética , Epigenômica , Rejuvenescimento , Envelhecimento/patologia , Animais , Relógios Biológicos , Regulação da Expressão Gênica no Desenvolvimento , Humanos
16.
Nature ; 597(7875): 256-262, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34381212

RESUMO

Loss of skeletal integrity during ageing and disease is associated with an imbalance in the opposing actions of osteoblasts and osteoclasts1. Here we show that intrinsic ageing of skeletal stem cells (SSCs)2 in mice alters signalling in the bone marrow niche and skews the differentiation of bone and blood lineages, leading to fragile bones that regenerate poorly. Functionally, aged SSCs have a decreased bone- and cartilage-forming potential but produce more stromal lineages that express high levels of pro-inflammatory and pro-resorptive cytokines. Single-cell RNA-sequencing studies link the functional loss to a diminished transcriptomic diversity of SSCs in aged mice, which thereby contributes to the transformation of the bone marrow niche. Exposure to a youthful circulation through heterochronic parabiosis or systemic reconstitution with young haematopoietic stem cells did not reverse the diminished osteochondrogenic activity of aged SSCs, or improve bone mass or skeletal healing parameters in aged mice. Conversely, the aged SSC lineage promoted osteoclastic activity and myeloid skewing by haematopoietic stem and progenitor cells, suggesting that the ageing of SSCs is a driver of haematopoietic ageing. Deficient bone regeneration in aged mice could only be returned to youthful levels by applying a combinatorial treatment of BMP2 and a CSF1 antagonist locally to fractures, which reactivated aged SSCs and simultaneously ablated the inflammatory, pro-osteoclastic milieu. Our findings provide mechanistic insights into the complex, multifactorial mechanisms that underlie skeletal ageing and offer prospects for rejuvenating the aged skeletal system.


Assuntos
Envelhecimento/patologia , Osso e Ossos/patologia , Senescência Celular , Inflamação/patologia , Nicho de Células-Tronco , Células-Tronco/patologia , Animais , Proteína Morfogenética Óssea 2/metabolismo , Regeneração Óssea , Linhagem da Célula , Feminino , Consolidação da Fratura , Hematopoese , Fator Estimulador de Colônias de Macrófagos/metabolismo , Masculino , Camundongos , Células Mieloides/citologia , Osteoclastos/citologia , Rejuvenescimento
17.
Nature ; 591(7848): 117-123, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33442062

RESUMO

The activation of mostly quiescent haematopoietic stem cells (HSCs) is a prerequisite for life-long production of blood cells1. This process requires major molecular adaptations to allow HSCs to meet the regulatory and metabolic requirements for cell division2-4. The mechanisms that govern cellular reprograming upon stem-cell activation, and the subsequent return of stem cells to quiescence, have not been fully characterized. Here we show that chaperone-mediated autophagy (CMA)5, a selective form of lysosomal protein degradation, is involved in sustaining HSC function in adult mice. CMA is required for protein quality control in stem cells and for the upregulation of fatty acid metabolism upon HSC activation. We find that CMA activity in HSCs decreases with age and show that genetic or pharmacological activation of CMA can restore the functionality of old mouse and human HSCs. Together, our findings provide mechanistic insights into a role for CMA in sustaining quality control, appropriate energetics and overall long-term HSC function. Our work suggests that CMA may be a promising therapeutic target for enhancing HSC function in conditions such as ageing or stem-cell transplantation.


Assuntos
Autofagia Mediada por Chaperonas/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Adulto , Idoso , Envelhecimento , Animais , Autorrenovação Celular , Células Cultivadas , Autofagia Mediada por Chaperonas/efeitos dos fármacos , Autofagia Mediada por Chaperonas/genética , Metabolismo Energético , Feminino , Glicólise , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Ácido Linoleico/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Rejuvenescimento , Adulto Jovem
18.
Nature ; 594(7861): 100-105, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33981041

RESUMO

Ageing of the immune system, or immunosenescence, contributes to the morbidity and mortality of the elderly1,2. To define the contribution of immune system ageing to organism ageing, here we selectively deleted Ercc1, which encodes a crucial DNA repair protein3,4, in mouse haematopoietic cells to increase the burden of endogenous DNA damage and thereby senescence5-7 in the immune system only. We show that Vav-iCre+/-;Ercc1-/fl mice were healthy into adulthood, then displayed premature onset of immunosenescence characterized by attrition and senescence of specific immune cell populations and impaired immune function, similar to changes that occur during ageing in wild-type mice8-10. Notably, non-lymphoid organs also showed increased senescence and damage, which suggests that senescent, aged immune cells can promote systemic ageing. The transplantation of splenocytes from Vav-iCre+/-;Ercc1-/fl or aged wild-type mice into young mice induced senescence in trans, whereas the transplantation of young immune cells attenuated senescence. The treatment of Vav-iCre+/-;Ercc1-/fl mice with rapamycin reduced markers of senescence in immune cells and improved immune function11,12. These data demonstrate that an aged, senescent immune system has a causal role in driving systemic ageing and therefore represents a key therapeutic target to extend healthy ageing.


Assuntos
Envelhecimento/imunologia , Envelhecimento/fisiologia , Sistema Imunitário/imunologia , Sistema Imunitário/fisiologia , Imunossenescência/imunologia , Imunossenescência/fisiologia , Especificidade de Órgãos/imunologia , Especificidade de Órgãos/fisiologia , Envelhecimento/efeitos dos fármacos , Envelhecimento/patologia , Animais , Dano ao DNA/imunologia , Dano ao DNA/fisiologia , Reparo do DNA/imunologia , Reparo do DNA/fisiologia , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Feminino , Envelhecimento Saudável/imunologia , Envelhecimento Saudável/fisiologia , Homeostase/imunologia , Homeostase/fisiologia , Sistema Imunitário/efeitos dos fármacos , Imunossenescência/efeitos dos fármacos , Masculino , Camundongos , Especificidade de Órgãos/efeitos dos fármacos , Rejuvenescimento , Sirolimo/farmacologia , Baço/citologia , Baço/transplante
19.
Nature ; 577(7790): 405-409, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31775156

RESUMO

Clinical trials using adult stem cells to regenerate damaged heart tissue continue to this day1,2, despite ongoing questions of efficacy and a lack of mechanistic understanding of the underlying biological effect3. The rationale for these cell therapy trials is derived from animal studies that show a modest but reproducible improvement in cardiac function in models of cardiac ischaemic injury4,5. Here we examine the mechanistic basis for cell therapy in mice after ischaemia-reperfusion injury, and find that-although heart function is enhanced-it is not associated with the production of new cardiomyocytes. Cell therapy improved heart function through an acute sterile immune response characterized by the temporal and regional induction of CCR2+ and CX3CR1+ macrophages. Intracardiac injection of two distinct types of adult stem cells, cells killed by freezing and thawing or a chemical inducer of the innate immune response all induced a similar regional accumulation of CCR2+ and CX3CR1+ macrophages, and provided functional rejuvenation to the heart after ischaemia-reperfusion injury. This selective macrophage response altered the activity of cardiac fibroblasts, reduced the extracellular matrix content in the border zone and enhanced the mechanical properties of the injured area. The functional benefit of cardiac cell therapy is thus due to an acute inflammatory-based wound-healing response that rejuvenates the infarcted area of the heart.


Assuntos
Imunidade Inata , Miócitos Cardíacos/imunologia , Transplante de Células-Tronco , Células-Tronco , Animais , Diferenciação Celular , Feminino , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/transplante , Rejuvenescimento
20.
Nature ; 583(7814): 127-132, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32555459

RESUMO

Cellular senescence is characterized by stable cell-cycle arrest and a secretory program that modulates the tissue microenvironment1,2. Physiologically, senescence serves as a tumour-suppressive mechanism that prevents the expansion of premalignant cells3,4 and has a beneficial role in wound-healing responses5,6. Pathologically, the aberrant accumulation of senescent cells generates an inflammatory milieu that leads to chronic tissue damage and contributes to diseases such as liver and lung fibrosis, atherosclerosis, diabetes and osteoarthritis1,7. Accordingly, eliminating senescent cells from damaged tissues in mice ameliorates the symptoms of these pathologies and even promotes longevity1,2,8-10. Here we test the therapeutic concept that chimeric antigen receptor (CAR) T cells that target senescent cells can be effective senolytic agents. We identify the urokinase-type plasminogen activator receptor (uPAR)11 as a cell-surface protein that is broadly induced during senescence and show that uPAR-specific CAR T cells efficiently ablate senescent cells in vitro and in vivo. CAR T cells that target uPAR extend the survival of mice with lung adenocarcinoma that are treated with a senescence-inducing combination of drugs, and restore tissue homeostasis in mice in which liver fibrosis is induced chemically or by diet. These results establish the therapeutic potential of senolytic CAR T cells for senescence-associated diseases.


Assuntos
Envelhecimento/patologia , Senescência Celular/imunologia , Cirrose Hepática/terapia , Longevidade/imunologia , Neoplasias Pulmonares/terapia , Receptores de Antígenos Quiméricos/imunologia , Rejuvenescimento , Linfócitos T/imunologia , Adenocarcinoma/imunologia , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Animais , Tetracloreto de Carbono , Feminino , Xenoenxertos , Humanos , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/imunologia , Cirrose Hepática/patologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Linfócitos T/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo
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