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1.
Proc Natl Acad Sci U S A ; 112(46): E6301-10, 2015 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-26578790

RESUMO

Chronic, low grade, sterile inflammation frequently accompanies aging and age-related diseases. Cellular senescence is associated with the production of proinflammatory chemokines, cytokines, and extracellular matrix (ECM) remodeling proteases, which comprise the senescence-associated secretory phenotype (SASP). We found a higher burden of senescent cells in adipose tissue with aging. Senescent human primary preadipocytes as well as human umbilical vein endothelial cells (HUVECs) developed a SASP that could be suppressed by targeting the JAK pathway using RNAi or JAK inhibitors. Conditioned medium (CM) from senescent human preadipocytes induced macrophage migration in vitro and inflammation in healthy adipose tissue and preadipocytes. When the senescent cells from which CM was derived had been treated with JAK inhibitors, the resulting CM was much less proinflammatory. The administration of JAK inhibitor to aged mice for 10 wk alleviated both adipose tissue and systemic inflammation and enhanced physical function. Our findings are consistent with a possible contribution of senescent cells and the SASP to age-related inflammation and frailty. We speculate that SASP inhibition by JAK inhibitors may contribute to alleviating frailty. Targeting the JAK pathway holds promise for treating age-related dysfunction.


Assuntos
Adipócitos/enzimologia , Senescência Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/enzimologia , Janus Quinases/antagonistas & inibidores , RNA Interferente Pequeno/farmacologia , Transdução de Sinais/efeitos dos fármacos , Adipócitos/citologia , Tecido Adiposo/citologia , Tecido Adiposo/enzimologia , Animais , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Senescência Celular/genética , Matriz Extracelular/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Janus Quinases/genética , Janus Quinases/metabolismo , Macrófagos/citologia , Macrófagos/enzimologia , Camundongos , RNA Interferente Pequeno/genética , Transdução de Sinais/genética
2.
Gut ; 65(7): 1165-74, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26061593

RESUMO

BACKGROUND AND OBJECTIVES: New-onset diabetes and concomitant weight loss occurring several months before the clinical presentation of pancreatic cancer (PC) appear to be paraneoplastic phenomena caused by tumour-secreted products. Our recent findings have shown exosomal adrenomedullin (AM) is important in development of diabetes in PC. Adipose tissue lipolysis might explain early onset weight loss in PC. We hypothesise that lipolysis-inducing cargo is carried in exosomes shed by PC and is responsible for the paraneoplastic effects. Therefore, in this study we investigate if exosomes secreted by PC induce lipolysis in adipocytes and explore the role of AM in PC-exosomes as the mediator of this lipolysis. DESIGN: Exosomes from patient-derived cell lines and from plasma of patients with PC and non-PC controls were isolated and characterised. Differentiated murine (3T3-L1) and human adipocytes were exposed to these exosomes to study lipolysis. Glycerol assay and western blotting were used to study lipolysis. Duolink Assay was used to study AM and adrenomedullin receptor (ADMR) interaction in adipocytes treated with exosomes. RESULTS: In murine and human adipocytes, we found that both AM and PC-exosomes promoted lipolysis, which was abrogated by ADMR blockade. AM interacted with its receptor on the adipocytes, activated p38 and extracellular signal-regulated (ERK1/2) mitogen-activated protein kinases and promoted lipolysis by phosphorylating hormone-sensitive lipase. PKH67-labelled PC-exosomes were readily internalised into adipocytes and involved both caveolin and macropinocytosis as possible mechanisms for endocytosis. CONCLUSIONS: PC-secreted exosomes induce lipolysis in subcutaneous adipose tissue; exosomal AM is a candidate mediator of this effect.


Assuntos
Adipócitos/metabolismo , Adrenomedulina/metabolismo , Exossomos/metabolismo , Lipólise , Sistema de Sinalização das MAP Quinases , Neoplasias Pancreáticas/metabolismo , Animais , Linhagem Celular Tumoral , Células Cultivadas , Endocitose/fisiologia , Glicerol/metabolismo , Humanos , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Receptores de Adrenomedulina/antagonistas & inibidores , Receptores de Adrenomedulina/metabolismo , Gordura Subcutânea/citologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
3.
Proc Natl Acad Sci U S A ; 108(1): 143-8, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21173238

RESUMO

Brown fat is specialized for energy expenditure and has therefore been proposed to function as a defense against obesity. Despite recent advances in delineating the transcriptional regulation of brown adipocyte differentiation, cellular lineage specification and developmental cues specifying brown-fat cell fate remain poorly understood. In this study, we identify and isolate a subpopulation of adipogenic progenitors (Sca-1(+)/CD45(-)/Mac1(-); referred to as Sca-1(+) progenitor cells, ScaPCs) residing in murine brown fat, white fat, and skeletal muscle. ScaPCs derived from different tissues possess unique molecular expression signatures and adipogenic capacities. Importantly, although the ScaPCs from interscapular brown adipose tissue (BAT) are constitutively committed brown-fat progenitors, Sca-1(+) cells from skeletal muscle and subcutaneous white fat are highly inducible to differentiate into brown-like adipocytes upon stimulation with bone morphogenetic protein 7 (BMP7). Consistent with these findings, human preadipocytes isolated from subcutaneous white fat also exhibit the greatest inducible capacity to become brown adipocytes compared with cells isolated from mesenteric or omental white fat. When muscle-resident ScaPCs are re-engrafted into skeletal muscle of syngeneic mice, BMP7-treated ScaPCs efficiently develop into adipose tissue with brown fat-specific characteristics. Importantly, ScaPCs from obesity-resistant mice exhibit markedly higher thermogenic capacity compared with cells isolated from obesity-prone mice. These data establish the molecular characteristics of tissue-resident adipose progenitors and demonstrate a dynamic interplay between these progenitors and inductive signals that act in concert to specify brown adipocyte development.


Assuntos
Adipócitos Marrons/fisiologia , Tecido Adiposo Branco/citologia , Antígenos Ly/metabolismo , Diferenciação Celular/fisiologia , Proteínas de Membrana/metabolismo , Músculo Esquelético/citologia , Células-Tronco/fisiologia , Adipócitos Marrons/citologia , Animais , Western Blotting , Proteína Morfogenética Óssea 7/metabolismo , Citometria de Fluxo , Imunofluorescência , Humanos , Imuno-Histoquímica , Camundongos , Termogênese/fisiologia
4.
bioRxiv ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38645053

RESUMO

In the last decade cellular senescence, a hallmark of aging, has come into focus for pharmacologically targeting aging processes. Senolytics are one of these interventive strategies that have advanced into clinical trials, creating an unmet need for minimally invasive biomarkers of senescent cell load to identify patients at need for senotherapy. We created a landscape of miRNA and mRNA expression in five human cell types induced to senescence in-vitro and provide proof-of-principle evidence that miRNA expression can track senescence burden dynamically in-vivo using transgenic p21 high senescent cell clearance in HFD fed mice. Finally, we profiled miRNA expression in seven different tissues, total plasma, and plasma derived EVs of young and 25 months old mice. In a systematic analysis, we identified 22 candidate senomiRs with potential to serve as circulating biomarkers of senescence not only in rodents, but also in upcoming human clinical senolytic trials.

5.
Proc Natl Acad Sci U S A ; 107(42): 18226-31, 2010 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-20921416

RESUMO

Body fat distribution is an important predictor of the metabolic consequences of obesity, but the cellular mechanisms regulating regional fat accumulation are unknown. We assessed the changes in adipocyte size (photomicrographs) and number in response to overfeeding in upper- and lower-body s.c. fat depots of 28 healthy, normal weight adults (15 men) age 29 ± 2 y. We analyzed how these changes relate to regional fat gain (dual energy X-ray absorptiometry and computed tomography) and baseline preadipocyte proliferation, differentiation [peroxisome proliferator-activated receptor-γ2 (PPARγ2) and CCAAT/enhancer binding protein-α (C/EBPα) mRNA]), and apoptotic response to TNF-α. Fat mass increased by 1.9 ± 0.2 kg in the upper body and 1.6 ± 0.1 kg in the lower body. Average abdominal s.c. adipocyte size increased by 0.16 ± 0.06 µg lipid per cell and correlated with relative upper-body fat gain (r = 0.74, P < 0.0001). However, lower-body fat responded to overfeeding by fat-cell hyperplasia, with adipocyte number increasing by 2.6 ± 0.9 × 10(9) cells (P < 0.01). We found no depot-differences in preadipocyte replication or apoptosis that would explain lower-body adipocyte hyperplasia and abdominal s.c. adipocyte hypertrophy. However, baseline PPARγ2 and C/EBPα mRNA were higher in abdominal than femoral s.c. preadipocytes (P < 0.005 and P < 0.03, respectively), consistent with the ability of abdominal s.c. adipocytes to achieve a larger size. Inherent differences in preadipocyte cell dynamics may contribute to the distinct responses of different fat depots to overfeeding, and fat-cell number increases in certain depots in adults after only 8 wk of increased food intake.


Assuntos
Tecido Adiposo/metabolismo , Ingestão de Energia , Absorciometria de Fóton , Adipócitos/metabolismo , Tecido Adiposo/citologia , Adulto , Composição Corporal , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Feminino , Humanos , Masculino , PPAR gama/genética , PPAR gama/metabolismo , Tomografia Computadorizada por Raios X , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
6.
Obesity (Silver Spring) ; 31(6): 1610-1619, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37194560

RESUMO

OBJECTIVE: The aim of this study was to determine the effect of age of obesity onset on senescence-related markers in abdominal (AB) and femoral (FEM) subcutaneous adipose tissue (SAT) before and after moderate (~10%) weight loss. METHODS: AB and FEM SAT were collected from human females with childhood-onset obesity (CO) or adult-onset obesity (AO) before and after diet- and exercise-induced weight loss. Immunofluorescence analysis of γH2AX/RAD51 (DNA damage/repair markers) and p53/p21 (senescence markers) was conducted in cultured preadipocytes, and senescence-associated ß-galactosidase (SA-ß-gal) activity was measured in SAT. RESULTS: CO had proportionately more AB and FEM preadipocytes with DNA damage (γH2AX+ ) and senescence markers (p53+ and/or p21+ ) than AO at baseline. The proportion of γH2AX+ FEM preadipocytes declined with weight loss in CO and was similar between groups after weight loss. The number of γH2AX foci in γH2AX+ preadipocytes decreased similarly between groups and regions with weight loss in parallel with an increase in RAD51. The proportion of p53+ and p21+ preadipocytes and SA-ß-gal+ cells in SAT did not change with weight loss, but the total p21 intensity in p53+ /p21+ FEM preadipocytes declined in AO. CONCLUSIONS: These results provide preliminary evidence that females with CO have an accelerated preadipocyte aging state that improves with weight loss in terms of DNA damage but not senescence.


Assuntos
Senescência Celular , Proteína Supressora de Tumor p53 , Feminino , Humanos , Adulto , Proteína Supressora de Tumor p53/farmacologia , Envelhecimento , Obesidade , Gordura Subcutânea
7.
EBioMedicine ; 77: 103912, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35292270

RESUMO

BACKGROUND: α-Klotho is a geroprotective protein that can attenuate or alleviate deleterious changes with ageing and disease. Declines in α-Klotho play a role in the pathophysiology of multiple diseases and age-related phenotypes. Pre-clinical evidence suggests that boosting α-Klotho holds therapeutic potential. However, readily clinically-translatable, practical strategies for increasing α-Klotho are not at hand. Here, we report that orally-active, clinically-translatable senolytics can increase α-Klotho in mice and humans. METHODS: We examined α-Klotho expression in three different human primary cell types co-cultured with conditioned medium (CM) from senescent or non-senescent cells with or without neutralizing antibodies. We assessed α-Klotho expression in aged, obese, and senescent cell-transplanted mice treated with vehicle or senolytics. We assayed urinary α-Klotho in patients with idiopathic pulmonary fibrosis (IPF) who were treated with the senolytic drug combination, Dasatinib plus Quercetin (D+Q). FINDINGS: We found exposure to the senescent cell secretome reduces α-Klotho in multiple nonsenescent human cell types. This was partially prevented by neutralizing antibodies against the senescence-associated secretory phenotype (SASP) factors, activin A and Interleukin 1α (IL-1α). Consistent with senescent cells' being a cause of decreased α-Klotho, transplanting senescent cells into younger mice reduced brain and urine α-Klotho. Selectively removing senescent cells genetically or pharmacologically increased α-Klotho in urine, kidney, and brain of mice with increased senescent cell burden, including naturally-aged, diet-induced obese (DIO), or senescent cell-transplanted mice. D+Q increased α-Klotho in urine of patients with IPF, a disease linked to cellular senescence. INTERPRETATION: Senescent cells cause reduced α-Klotho, partially due to their production of activin A and IL-1α. Targeting senescent cells boosts α-Klotho in mice and humans. Thus, clearing senescent cells restores α-Klotho, potentially opening a novel, translationally-feasible avenue for developing orally-active small molecule, α-Klotho-enhancing clinical interventions. Furthermore, urinary α-Klotho may prove to be a useful test for following treatments in senolytic clinical trials. FUNDING: This work was supported by National Institute of Health grants AG013925 (J.L.K.), AG062413 (J.L.K., S.K.), AG044271 (N.M.), AG013319 (N.M.), and the Translational Geroscience Network (AG061456: J.L.K., T.T., N.M., S.B.K., S.K.), Robert and Arlene Kogod (J.L.K.), the Connor Group (J.L.K.), Robert J. and Theresa W. Ryan (J.L.K.), and the Noaber Foundation (J.L.K.). The previous IPF clinical trial was supported by the Claude D. Pepper Older Americans Independence Centers at WFSM (AG021332: J.N.J., S.B.K.), UTHSCA (AG044271: A.M.N.), and the Translational Geroscience Network.


Assuntos
Envelhecimento , Senoterapia , Idoso , Animais , Encéfalo , Senescência Celular , Humanos , Camundongos , Quercetina/farmacologia
8.
Cell Rep ; 36(5): 109481, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34348145

RESUMO

Preadipocytes dynamically produce sensory cilia. However, the role of primary cilia in preadipocyte differentiation and adipose homeostasis remains poorly understood. We previously identified transition fiber component FBF1 as an essential player in controlling selective cilia import. Here, we establish Fbf1tm1a/tm1a mice and discover that Fbf1tm1a/tm1a mice develop severe obesity, but surprisingly, are not predisposed to adverse metabolic complications. Obese Fbf1tm1a/tm1a mice possess unexpectedly healthy white fat tissue characterized by spontaneous upregulated beiging, hyperplasia but not hypertrophy, and low inflammation along the lifetime. Mechanistically, FBF1 governs preadipocyte differentiation by constraining the beiging program through an AKAP9-dependent, cilia-regulated PKA signaling, while recruiting the BBS chaperonin to transition fibers to suppress the hedgehog signaling-dependent adipogenic program. Remarkably, obese Fbf1tm1a/tm1a mice further fed a high-fat diet are protected from diabetes and premature death. We reveal a central role for primary cilia in the fate determination of preadipocytes and the generation of metabolically healthy fat tissue.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/deficiência , Tecido Adiposo Bege/metabolismo , Tecido Adiposo Branco/metabolismo , Células 3T3-L1 , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adipócitos/metabolismo , Adipogenia , Animais , Respiração Celular , Cílios/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Feminino , Fibroblastos/metabolismo , Proteínas Hedgehog/metabolismo , Homozigoto , Humanos , Hiperfagia/complicações , Hiperfagia/patologia , Hiperplasia , Inflamação/patologia , Masculino , Síndrome Metabólica/complicações , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/metabolismo , Obesidade/complicações , Transdução de Sinais , Fatores de Transcrição/metabolismo
9.
Aging (Albany NY) ; 13(18): 21838-21854, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531331

RESUMO

Senescent cells, which arise due to damage-associated signals, are apoptosis-resistant and can express a pro-inflammatory, tissue-destructive senescence-associated secretory phenotype (SASP). We recently reported that a component of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surface protein, S1, can amplify the SASP of senescent cultured human cells and that a related mouse ß-coronavirus, mouse hepatitis virus (MHV), increases SASP factors and senescent cell burden in infected mice. Here, we show that SARS-CoV-2 induces senescence in human non-senescent cells and exacerbates the SASP in human senescent cells through Toll-like receptor-3 (TLR-3). TLR-3, which senses viral RNA, was increased in human senescent compared to non-senescent cells. Notably, genetically or pharmacologically inhibiting TLR-3 prevented senescence induction and SASP amplification by SARS-CoV-2 or Spike pseudotyped virus. While an artificial TLR-3 agonist alone was not sufficient to induce senescence, it amplified the SASP in senescent human cells. Consistent with these findings, lung p16INK4a+ senescent cell burden was higher in patients who died from acute SARS-CoV-2 infection than other causes. Our results suggest that induction of cellular senescence and SASP amplification through TLR-3 contribute to SARS-CoV-2 morbidity, indicating that clinical trials of senolytics and/or SASP/TLR-3 inhibitors for alleviating acute and long-term SARS-CoV-2 sequelae are warranted.


Assuntos
COVID-19/virologia , Senescência Celular , SARS-CoV-2/patogenicidade , Receptor 3 Toll-Like/metabolismo , Envelhecimento , Animais , Apoptose , COVID-19/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Humanos , Inflamação , Pulmão/metabolismo , Camundongos , Fenótipo , Proteínas Virais , Tratamento Farmacológico da COVID-19
10.
Science ; 373(6552)2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34103349

RESUMO

The COVID-19 pandemic has revealed the pronounced vulnerability of the elderly and chronically ill to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced morbidity and mortality. Cellular senescence contributes to inflammation, multiple chronic diseases, and age-related dysfunction, but effects on responses to viral infection are unclear. Here, we demonstrate that senescent cells (SnCs) become hyper-inflammatory in response to pathogen-associated molecular patterns (PAMPs), including SARS-CoV-2 spike protein-1, increasing expression of viral entry proteins and reducing antiviral gene expression in non-SnCs through a paracrine mechanism. Old mice acutely infected with pathogens that included a SARS-CoV-2-related mouse ß-coronavirus experienced increased senescence and inflammation, with nearly 100% mortality. Targeting SnCs by using senolytic drugs before or after pathogen exposure significantly reduced mortality, cellular senescence, and inflammatory markers and increased antiviral antibodies. Thus, reducing the SnC burden in diseased or aged individuals should enhance resilience and reduce mortality after viral infection, including that of SARS-CoV-2.


Assuntos
Envelhecimento , Senescência Celular/efeitos dos fármacos , Infecções por Coronavirus/mortalidade , Flavonóis/uso terapêutico , Moléculas com Motivos Associados a Patógenos/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Animais , COVID-19/imunologia , COVID-19/mortalidade , Linhagem Celular , Infecções por Coronavirus/imunologia , Dasatinibe/farmacologia , Dasatinibe/uso terapêutico , Feminino , Flavonóis/farmacologia , Regulação da Expressão Gênica , Humanos , Lipopolissacarídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Vírus da Hepatite Murina/imunologia , Quercetina/farmacologia , Quercetina/uso terapêutico , Receptores de Coronavírus/genética , Receptores de Coronavírus/metabolismo , Organismos Livres de Patógenos Específicos , Tratamento Farmacológico da COVID-19
11.
Cell Metab ; 29(5): 1061-1077.e8, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30612898

RESUMO

Cellular senescence entails a stable cell-cycle arrest and a pro-inflammatory secretory phenotype, which contributes to aging and age-related diseases. Obesity is associated with increased senescent cell burden and neuropsychiatric disorders, including anxiety and depression. To investigate the role of senescence in obesity-related neuropsychiatric dysfunction, we used the INK-ATTAC mouse model, from which p16Ink4a-expressing senescent cells can be eliminated, and senolytic drugs dasatinib and quercetin. We found that obesity results in the accumulation of senescent glial cells in proximity to the lateral ventricle, a region in which adult neurogenesis occurs. Furthermore, senescent glial cells exhibit excessive fat deposits, a phenotype we termed "accumulation of lipids in senescence." Clearing senescent cells from high fat-fed or leptin receptor-deficient obese mice restored neurogenesis and alleviated anxiety-related behavior. Our study provides proof-of-concept evidence that senescent cells are major contributors to obesity-induced anxiety and that senolytics are a potential new therapeutic avenue for treating neuropsychiatric disorders.


Assuntos
Ansiedade/etiologia , Senescência Celular/efeitos dos fármacos , Neurogênese , Obesidade/complicações , Animais , Ansiedade/tratamento farmacológico , Astrócitos/metabolismo , Comportamento Animal/efeitos dos fármacos , Encéfalo/citologia , Encéfalo/embriologia , Células Cultivadas , Inibidor p16 de Quinase Dependente de Ciclina/genética , Dasatinibe/farmacologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Feminino , Fibroblastos/metabolismo , Gotículas Lipídicas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Obesidade/etiologia , Quercetina/farmacologia , Tacrolimo/análogos & derivados , Tacrolimo/farmacologia , Tacrolimo/uso terapêutico
12.
EBioMedicine ; 47: 446-456, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31542391

RESUMO

BACKGROUND: Senescent cells, which can release factors that cause inflammation and dysfunction, the senescence-associated secretory phenotype (SASP), accumulate with ageing and at etiological sites in multiple chronic diseases. Senolytics, including the combination of Dasatinib and Quercetin (D + Q), selectively eliminate senescent cells by transiently disabling pro-survival networks that defend them against their own apoptotic environment. In the first clinical trial of senolytics, D + Q improved physical function in patients with idiopathic pulmonary fibrosis (IPF), a fatal senescence-associated disease, but to date, no peer-reviewed study has directly demonstrated that senolytics decrease senescent cells in humans. METHODS: In an open label Phase 1 pilot study, we administered 3 days of oral D 100 mg and Q 1000 mg to subjects with diabetic kidney disease (N = 9; 68·7 ±â€¯3·1 years old; 2 female; BMI:33·9 ±â€¯2·3 kg/m2; eGFR:27·0 ±â€¯2·1 mL/min/1·73m2). Adipose tissue, skin biopsies, and blood were collected before and 11 days after completing senolytic treatment. Senescent cell and macrophage/Langerhans cell markers and circulating SASP factors were assayed. FINDINGS: D + Q reduced adipose tissue senescent cell burden within 11 days, with decreases in p16INK4A-and p21CIP1-expressing cells, cells with senescence-associated ß-galactosidase activity, and adipocyte progenitors with limited replicative potential. Adipose tissue macrophages, which are attracted, anchored, and activated by senescent cells, and crown-like structures were decreased. Skin epidermal p16INK4A+ and p21CIP1+ cells were reduced, as were circulating SASP factors, including IL-1α, IL-6, and MMPs-9 and -12. INTERPRETATION: "Hit-and-run" treatment with senolytics, which in the case of D + Q have elimination half-lives <11 h, significantly decreases senescent cell burden in humans. FUND: NIH and Foundations. ClinicalTrials.gov Identifier: NCT02848131. Senescence, Frailty, and Mesenchymal Stem Cell Functionality in Chronic Kidney Disease: Effect of Senolytic Agents.


Assuntos
Senescência Celular/efeitos dos fármacos , Dasatinibe/farmacologia , Nefropatias Diabéticas/metabolismo , Quercetina/farmacologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Idoso , Biomarcadores , Biópsia , Ensaios Clínicos Fase I como Assunto , Dasatinibe/uso terapêutico , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/tratamento farmacológico , Quimioterapia Combinada , Feminino , Humanos , Imuno-Histoquímica , Testes de Função Renal , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Quercetina/uso terapêutico
13.
Nat Med ; 24(8): 1246-1256, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29988130

RESUMO

Physical function declines in old age, portending disability, increased health expenditures, and mortality. Cellular senescence, leading to tissue dysfunction, may contribute to these consequences of aging, but whether senescence can directly drive age-related pathology and be therapeutically targeted is still unclear. Here we demonstrate that transplanting relatively small numbers of senescent cells into young mice is sufficient to cause persistent physical dysfunction, as well as to spread cellular senescence to host tissues. Transplanting even fewer senescent cells had the same effect in older recipients and was accompanied by reduced survival, indicating the potency of senescent cells in shortening health- and lifespan. The senolytic cocktail, dasatinib plus quercetin, which causes selective elimination of senescent cells, decreased the number of naturally occurring senescent cells and their secretion of frailty-related proinflammatory cytokines in explants of human adipose tissue. Moreover, intermittent oral administration of senolytics to both senescent cell-transplanted young mice and naturally aged mice alleviated physical dysfunction and increased post-treatment survival by 36% while reducing mortality hazard to 65%. Our study provides proof-of-concept evidence that senescent cells can cause physical dysfunction and decreased survival even in young mice, while senolytics can enhance remaining health- and lifespan in old mice.


Assuntos
Dasatinibe/farmacologia , Longevidade/efeitos dos fármacos , Quercetina/farmacologia , Tecido Adiposo/metabolismo , Animais , Transplante de Células , Senescência Celular/efeitos dos fármacos , Citocinas/metabolismo , Dieta Hiperlipídica , Mediadores da Inflamação/metabolismo , Camundongos Endogâmicos C57BL , Estresse Fisiológico/efeitos dos fármacos , Análise de Sobrevida
14.
Diabetes ; 55(9): 2571-8, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16936206

RESUMO

Fat depots vary in size, function, and potential contribution to disease. Since fat tissue turns over throughout life, preadipocyte characteristics could contribute to this regional variation. To address whether preadipocytes from different depots are distinct, we produced preadipocyte strains from single abdominal subcutaneous, mesenteric, and omental human preadipocytes by stably expressing human telomere reverse transcriptase (hTERT). These strains could be subcultured repeatedly and retained capacity for differentiation, while primary preadipocyte adipogenesis and replication declined with subculturing. Primary omental preadipocytes, in which telomeres were longest, replicated more slowly than mesenteric or abdominal subcutaneous preadipocytes. Even after 40 population doublings, replication, abundance of the rapidly replicating preadipocyte subtype, and resistance to tumor necrosis factor alpha-induced apoptosis were highest in subcutaneous, intermediate in mesenteric, and lowest in omental hTERT-expressing strains, as in primary preadipocytes. Subcutaneous hTERT-expressing strains accumulated more lipid and expressed more adipocyte fatty acid-binding protein (aP2), peroxisome proliferator-activated receptor gamma2, and CCAAT/enhancer-binding protein alpha than omental cells, as in primary preadipocytes, while hTERT abundance was similar. Thus, despite dividing 40 population doublings, hTERT strains derived from single preadipocytes retained fat depot-specific cell dynamic characteristics, consistent with heritable processes contributing to regional variation in fat tissue function.


Assuntos
Adipócitos/citologia , Gordura Abdominal/citologia , Tecido Adiposo/citologia , Adolescente , Adulto , Idoso , Apoptose/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Feminino , Humanos , Masculino , Mesentério/citologia , Pessoa de Meia-Idade , Omento/citologia , Células-Tronco/citologia , Gordura Subcutânea/citologia , Telomerase/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
15.
Aging (Albany NY) ; 9(3): 955-963, 2017 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-28273655

RESUMO

Senescent cells accumulate with aging and at sites of pathology in multiple chronic diseases. Senolytics are drugs that selectively promote apoptosis of senescent cells by temporarily disabling the pro-survival pathways that enable senescent cells to resist the pro-apoptotic, pro-inflammatory factors that they themselves secrete. Reducing senescent cell burden by genetic approaches or by administering senolytics delays or alleviates multiple age- and disease-related adverse phenotypes in preclinical models. Reported senolytics include dasatinib, quercetin, navitoclax (ABT263), and piperlongumine. Here we report that fisetin, a naturally-occurring flavone with low toxicity, and A1331852 and A1155463, selective BCL-XL inhibitors that may have less hematological toxicity than the less specific BCL-2 family inhibitor navitoclax, are senolytic. Fisetin selectively induces apoptosis in senescent but not proliferating human umbilical vein endothelial cells (HUVECs). It is not senolytic in senescent IMR90 cells, a human lung fibroblast strain, or primary human preadipocytes. A1331852 and A1155463 are senolytic in HUVECs and IMR90 cells, but not preadipocytes. These agents may be better candidates for eventual translation into clinical interventions than some existing senolytics, such as navitoclax, which is associated with hematological toxicity.


Assuntos
Antineoplásicos/farmacologia , Senescência Celular/efeitos dos fármacos , Flavonoides/farmacologia , Proteína bcl-X/antagonistas & inibidores , Compostos de Anilina/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Flavonóis , Humanos , Sulfonamidas/farmacologia
16.
Aging Cell ; 15(3): 428-35, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26711051

RESUMO

Clearing senescent cells extends healthspan in mice. Using a hypothesis-driven bioinformatics-based approach, we recently identified pro-survival pathways in human senescent cells that contribute to their resistance to apoptosis. This led to identification of dasatinib (D) and quercetin (Q) as senolytics, agents that target some of these pathways and induce apoptosis preferentially in senescent cells. Among other pro-survival regulators identified was Bcl-xl. Here, we tested whether the Bcl-2 family inhibitors, navitoclax (N) and TW-37 (T), are senolytic. Like D and Q, N is senolytic in some, but not all types of senescent cells: N reduced viability of senescent human umbilical vein epithelial cells (HUVECs), IMR90 human lung fibroblasts, and murine embryonic fibroblasts (MEFs), but not human primary preadipocytes, consistent with our previous finding that Bcl-xl siRNA is senolytic in HUVECs, but not preadipocytes. In contrast, T had little senolytic activity. N targets Bcl-2, Bcl-xl, and Bcl-w, while T targets Bcl-2, Bcl-xl, and Mcl-1. The combination of Bcl-2, Bcl-xl, and Bcl-w siRNAs was senolytic in HUVECs and IMR90 cells, while combination of Bcl-2, Bcl-xl, and Mcl-1 siRNAs was not. Susceptibility to N correlated with patterns of Bcl-2 family member proteins in different types of human senescent cells, as has been found in predicting response of cancers to N. Thus, N is senolytic and acts in a potentially predictable cell type-restricted manner. The hypothesis-driven, bioinformatics-based approach we used to discover that dasatinib (D) and quercetin (Q) are senolytic can be extended to increase the repertoire of senolytic drugs, including additional cell type-specific senolytic agents.


Assuntos
Compostos de Anilina/farmacologia , Apoptose/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sulfonamidas/farmacologia , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/metabolismo , Dasatinibe/farmacologia , Embrião de Mamíferos/citologia , Endonucleases/deficiência , Endonucleases/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Modelos Biológicos , Quercetina/farmacologia , Interferência de RNA/efeitos dos fármacos , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos
17.
Obesity (Silver Spring) ; 23(5): 989-99, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25864718

RESUMO

OBJECTIVE: Visceral white adipose tissue (WAT) expansion and macrophage accumulation are associated with metabolic dysfunction. Visceral WAT typically shows greater macrophage infiltration. Preadipocytes show varying proinflammatory expression profiles among WAT depots. The objective was to examine the secretomes and chemoattractive properties of preadipocytes from visceral and subcutaneous WAT. METHODS: A label-free quantitative proteomics approach was applied to study secretomes of subcutaneous and omental preadipocytes from obese subjects. Enzyme-linked immunosorbent assays and chemotaxis assays were used to confirm proinflammatory chemokine secretion between depots. RESULTS: Preadipocyte secretomes showed greater variation between depots than did intracellular protein expression. Chemokines were the most differentially secreted proteins. Omental preadipocytes induced chemoattraction of macrophages and monocytes. Neutralizing antibodies to the identified chemokines reduced macrophage/monocyte chemoattraction. Subcutaneous preadipocytes treated with interleukin-6 (IL-6) resembled omental preadipocytes in terms of chemokine secretion and macrophage/monocyte chemoattraction. Janus-activated kinase (JAK1/2) protein expression, which transduces IL-6 signaling, was higher in omental than subcutaneous preadipocytes and WAT. Inhibiting JAK in omental preadipocytes decreased chemokine secretion and macrophage/monocyte chemoattraction to levels closer to that observed in subcutaneous preadipocytes. CONCLUSIONS: Secretomes of omental and subcutaneous preadipocytes are distinct, with the former inducing more macrophage/monocyte chemoattraction, in part through IL-6/JAK-mediated signaling.


Assuntos
Adipócitos Brancos/metabolismo , Inflamação/metabolismo , Obesidade/metabolismo , Omento/metabolismo , Gordura Subcutânea/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Interleucina-6/metabolismo , Gordura Intra-Abdominal/metabolismo , Macrófagos/metabolismo , Monócitos/metabolismo , Proteínas/metabolismo
18.
Elife ; 4: e12997, 2015 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-26687007

RESUMO

Senescent cells accumulate in fat with aging. We previously found genetic clearance of senescent cells from progeroid INK-ATTAC mice prevents lipodystrophy. Here we show that primary human senescent fat progenitors secrete activin A and directly inhibit adipogenesis in non-senescent progenitors. Blocking activin A partially restored lipid accumulation and expression of key adipogenic markers in differentiating progenitors exposed to senescent cells. Mouse fat tissue activin A increased with aging. Clearing senescent cells from 18-month-old naturally-aged INK-ATTAC mice reduced circulating activin A, blunted fat loss, and enhanced adipogenic transcription factor expression within 3 weeks. JAK inhibitor suppressed senescent cell activin A production and blunted senescent cell-mediated inhibition of adipogenesis. Eight weeks-treatment with ruxolitinib, an FDA-approved JAK1/2 inhibitor, reduced circulating activin A, preserved fat mass, reduced lipotoxicity, and increased insulin sensitivity in 22-month-old mice. Our study indicates targeting senescent cells or their products may alleviate age-related dysfunction of progenitors, adipose tissue, and metabolism.


Assuntos
Adipogenia , Senescência Celular , Células-Tronco/fisiologia , Ativinas/metabolismo , Animais , Humanos , Camundongos
19.
Aging Cell ; 14(4): 644-58, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25754370

RESUMO

The healthspan of mice is enhanced by killing senescent cells using a transgenic suicide gene. Achieving the same using small molecules would have a tremendous impact on quality of life and the burden of age-related chronic diseases. Here, we describe the rationale for identification and validation of a new class of drugs termed senolytics, which selectively kill senescent cells. By transcript analysis, we discovered increased expression of pro-survival networks in senescent cells, consistent with their established resistance to apoptosis. Using siRNA to silence expression of key nodes of this network, including ephrins (EFNB1 or 3), PI3Kδ, p21, BCL-xL, or plasminogen-activated inhibitor-2, killed senescent cells, but not proliferating or quiescent, differentiated cells. Drugs targeting these same factors selectively killed senescent cells. Dasatinib eliminated senescent human fat cell progenitors, while quercetin was more effective against senescent human endothelial cells and mouse BM-MSCs. The combination of dasatinib and quercetin was effective in eliminating senescent MEFs. In vivo, this combination reduced senescent cell burden in chronologically aged, radiation-exposed, and progeroid Ercc1(-/Δ) mice. In old mice, cardiac function and carotid vascular reactivity were improved 5 days after a single dose. Following irradiation of one limb in mice, a single dose led to improved exercise capacity for at least 7 months following drug treatment. Periodic drug administration extended healthspan in Ercc1(-/∆) mice, delaying age-related symptoms and pathology, osteoporosis, and loss of intervertebral disk proteoglycans. These results demonstrate the feasibility of selectively ablating senescent cells and the efficacy of senolytics for alleviating symptoms of frailty and extending healthspan.


Assuntos
Envelhecimento/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Dasatinibe/farmacologia , Osteoporose/prevenção & controle , Quercetina/farmacologia , Transcriptoma , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipócitos/patologia , Envelhecimento/genética , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/patologia , Senescência Celular/genética , Classe I de Fosfatidilinositol 3-Quinases , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Combinação de Medicamentos , Endonucleases/genética , Endonucleases/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Efrinas/genética , Efrinas/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Perfilação da Expressão Gênica , Coração/efeitos dos fármacos , Coração/fisiopatologia , Disco Intervertebral/química , Disco Intervertebral/efeitos dos fármacos , Disco Intervertebral/patologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Knockout , Osteoporose/genética , Osteoporose/metabolismo , Osteoporose/patologia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inibidor 2 de Ativador de Plasminogênio/genética , Inibidor 2 de Ativador de Plasminogênio/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
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