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1.
Nat Commun ; 11(1): 4413, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887883

RESUMO

The molecular signatures of cells in the brain have been revealed in unprecedented detail, yet the ageing-associated genome-wide expression changes that may contribute to neurovascular dysfunction in neurodegenerative diseases remain elusive. Here, we report zonation-dependent transcriptomic changes in aged mouse brain endothelial cells (ECs), which prominently implicate altered immune/cytokine signaling in ECs of all vascular segments, and functional changes impacting the blood-brain barrier (BBB) and glucose/energy metabolism especially in capillary ECs (capECs). An overrepresentation of Alzheimer disease (AD) GWAS genes is evident among the human orthologs of the differentially expressed genes of aged capECs, while comparative analysis revealed a subset of concordantly downregulated, functionally important genes in human AD brains. Treatment with exenatide, a glucagon-like peptide-1 receptor agonist, strongly reverses aged mouse brain EC transcriptomic changes and BBB leakage, with associated attenuation of microglial priming. We thus revealed transcriptomic alterations underlying brain EC ageing that are complex yet pharmacologically reversible.


Assuntos
Envelhecimento/patologia , Barreira Hematoencefálica , Encéfalo/fisiopatologia , Células Endoteliais/metabolismo , Exenatida/farmacologia , Doença de Alzheimer/fisiopatologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiopatologia , Capilares/metabolismo , Células Cultivadas , Humanos , Camundongos , Microglia/efeitos dos fármacos , Doenças Neurodegenerativas/fisiopatologia , Transcriptoma/efeitos dos fármacos
2.
PLoS One ; 15(8): e0236986, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866198

RESUMO

White matter hyperintensities (WMHs) are among the most commonly observed marker of cerebrovascular disease. Age is a key risk factor for WMH development. Cardiorespiratory fitness (CRF) is associated with increased vessel compliance, but it remains unknown if high CRF affects WMH volume. This study explored the effects of CRF on WMH volume in community-dwelling older adults. We further tested the possibility of an interaction between CRF and age on WMH volume. Participants were 76 adults between the ages of 59 and 77 (mean age = 65.36 years, SD = 3.92) who underwent a maximal graded exercise test and structural brain imaging. Results indicated that age was a predictor of WMH volume (beta = .32, p = .015). However, an age-by-CRF interaction was observed such that higher CRF was associated with lower WMH volume in older participants (beta = -.25, p = .040). Our findings suggest that higher levels of aerobic fitness may protect cerebrovascular health in older adults.


Assuntos
Envelhecimento/patologia , Envelhecimento/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Substância Branca/diagnóstico por imagem , Idoso , Circulação Cerebrovascular/fisiologia , Transtornos Cerebrovasculares/diagnóstico por imagem , Transtornos Cerebrovasculares/patologia , Transtornos Cerebrovasculares/fisiopatologia , Teste de Esforço , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Fatores de Risco , Substância Branca/irrigação sanguínea , Substância Branca/patologia
3.
Science ; 369(6506)2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32820093

RESUMO

In developed countries, the leading causes of blindness such as diabetic retinopathy are characterized by disorganized vasculature that can become fibrotic. Although many such pathological vessels often naturally regress and spare sight-threatening complications, the underlying mechanisms remain unknown. Here, we used orthogonal approaches in human patients with proliferative diabetic retinopathy and a mouse model of ischemic retinopathies to identify an unconventional role for neutrophils in vascular remodeling during late-stage sterile inflammation. Senescent vasculature released a secretome that attracted neutrophils and triggered the production of neutrophil extracellular traps (NETs). NETs ultimately cleared diseased endothelial cells and remodeled unhealthy vessels. Genetic or pharmacological inhibition of NETosis prevented the regression of senescent vessels and prolonged disease. Thus, clearance of senescent retinal blood vessels leads to reparative vascular remodeling.


Assuntos
Envelhecimento/patologia , Retinopatia Diabética/patologia , Armadilhas Extracelulares/imunologia , Vasos Retinianos/patologia , Animais , Senescência Celular , Retinopatia Diabética/imunologia , Modelos Animais de Doenças , Células Endoteliais/imunologia , Células Endoteliais/patologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/imunologia , Vasos Retinianos/imunologia
4.
J Nutr Health Aging ; 24(7): 685-691, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32744561

RESUMO

A new coronavirus, called SARS-CoV-2, was identified in Wuhan, China, in December 2019. The SARS-CoV-2 spread very rapidly, causing a global pandemic, Coronavirus Disease 2019 (COVID-19). Older adults have higher peak of viral load and, especially those with comorbidities, had higher COVID-19-related fatality rates than younger adults. In this Perspective paper, we summarize current knowledge about SARS-CoV-2 and aging, in order to understand why older people are more affected by COVID-19. We discuss about the possibility that the so-called "immunosenescence" and "inflammaging" processes, already present in a fraction of frail older adults, could allow the immune escape of SARS-CoV-2 leading to COVID-19 serious complications. Finally, we propose to use geroscience approaches to the field of COVID-19.


Assuntos
Envelhecimento , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Geriatria , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Virologia , Idoso , Envelhecimento/imunologia , Envelhecimento/patologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Pandemias
5.
J Med Life ; 13(2): 116-118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32728402

RESUMO

The role of the renin-angiotensin system in hypertension and end-organ damage has long been recognized. Angiotensin l converting enzyme inhibitors are superior to other antihypertensive agents in protecting the kidney against progressive deterioration, even in normotensive persons. Likewise, angiotensin II type 1 receptor antagonists improve or even reverse glomerulosclerosis in rat animal models. These findings suggest that Angiotensin II has nonhemodynamic effects in progressive renal disease. The renin-angiotensin system is now recognized to be linked to the induction of plasminogen activator-inhibitor-1, possibly via the AT4 receptor, thus promoting both thrombosis and fibrosis. Interactions of the renin-angiotensin system with aldosterone and bradykinin may impact both blood pressure and tissue injury. The beneficial effect on renal fibrosis of inhibiting the renin-angiotensin system likely reflects the central role that angiotensin has in regulating renal function and structure by its various actions. This article explores the renin-angiotensin-aldosterone system with plasminogen activator-inhibitor-1 interaction and the potential significance of these interactions in the pathogenesis of progressive renal disease and remodeling of renal sclerosis.


Assuntos
Nefropatias/patologia , Envelhecimento/patologia , Aldosterona/metabolismo , Angiotensinas/metabolismo , Animais , Humanos , Indução de Remissão , Sistema Renina-Angiotensina
6.
PLoS Genet ; 16(7): e1008835, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32644988

RESUMO

In most organisms, dietary restriction (DR) increases lifespan. However, several studies have found that genotypes within the same species vary widely in how they respond to DR. To explore the mechanisms underlying this variation, we exposed 178 inbred Drosophila melanogaster lines to a DR or ad libitum (AL) diet, and measured a panel of 105 metabolites under both diets. Twenty four out of 105 metabolites were associated with the magnitude of the lifespan response. These included proteinogenic amino acids and metabolites involved in α-ketoglutarate (α-KG)/glutamine metabolism. We confirm the role of α-KG/glutamine synthesis pathways in the DR response through genetic manipulations. We used covariance network analysis to investigate diet-dependent interactions between metabolites, identifying the essential amino acids threonine and arginine as "hub" metabolites in the DR response. Finally, we employ a novel metabolic and genetic bipartite network analysis to reveal multiple genes that influence DR lifespan response, some of which have not previously been implicated in DR regulation. One of these is CCHa2R, a gene that encodes a neuropeptide receptor that influences satiety response and insulin signaling. Across the lines, variation in an intronic single nucleotide variant of CCHa2R correlated with variation in levels of five metabolites, all of which in turn were correlated with DR lifespan response. Inhibition of adult CCHa2R expression extended DR lifespan of flies, confirming the role of CCHa2R in lifespan response. These results provide support for the power of combined genomic and metabolomic analysis to identify key pathways underlying variation in this complex quantitative trait.


Assuntos
Envelhecimento/genética , Proteínas de Drosophila/genética , Longevidade/genética , Metaboloma/genética , Receptores Acoplados a Proteínas-G/genética , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Restrição Calórica , Dieta , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/genética , Insulina/genética , Metabolômica , Mutação/genética , Transdução de Sinais/genética
7.
PLoS One ; 15(7): e0232564, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726309

RESUMO

BACKGROUND: The identity and spatial distribution of prostatic cell types has been determined in humans but not in dogs, even though aging- and prostate-related voiding disorders are common in both species and mechanistic factors, such as prostatic collagen accumulation, appear to be shared between species. In this publication we characterize the regional distribution of prostatic cell types in the young intact dog to enable comparisons with human and mice and we examine how the cellular source of procollagen 1A1 changes with age in intact male dogs. METHODS: A multichotomous decision tree involving sequential immunohistochemical stains was validated for use in dog and used to identify specific prostatic cell types and determine their distribution in the capsule, peripheral, periurethral and urethral regions of the young intact canine prostate. Prostatic cells identified using this technique include perivascular smooth muscle cells, pericytes, endothelial cells, luminal, intermediate, and basal epithelial cells, neuroendocrine cells, myofibroblasts, fibroblasts, fibrocytes, and other hematolymphoid cells. To enhance rigor and transparency, all high resolution images (representative images shown in the figures and biological replicates) are available through the GUDMAP database at https://doi.org/10.25548/16-WMM4. RESULTS: The prostatic peripheral region harbors the largest proportion of epithelial cells. Aging does not change the density of hematolymphoid cells, fibroblasts, and myofibroblasts in the peripheral region or in the fibromuscular capsule, regions where we previously observed aging- and androgen-mediated increases in prostatic collagen abundance Instead, we observed aging-related changes the procollagen 1A1 positive prostatic cell identity from a myofibroblast to a fibroblast. CONCLUSIONS: Hematolymphoid cells and myofibroblasts are often identified as sources of collagen in tissues prone to aging-related fibrosis. We show that these are not the likely sources of pathological collagen synthesis in older intact male dogs. Instead, we identify an aging-related shift in the prostatic cell type producing procollagen 1A1 that will help direct development of cell type and prostate appropriate therapeutics for collagen accumulation.


Assuntos
Envelhecimento/fisiologia , Fibroblastos/metabolismo , Miofibroblastos/metabolismo , Pró-Colágeno/biossíntese , Próstata/citologia , Bexiga Urinária/fisiopatologia , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Suscetibilidade a Doenças , Cães , Imuno-Histoquímica , Masculino , Próstata/metabolismo , Próstata/patologia
8.
Nature ; 583(7816): 425-430, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612231

RESUMO

The vascular interface of the brain, known as the blood-brain barrier (BBB), is understood to maintain brain function in part via its low transcellular permeability1-3. Yet, recent studies have demonstrated that brain ageing is sensitive to circulatory proteins4,5. Thus, it is unclear whether permeability to individually injected exogenous tracers-as is standard in BBB studies-fully represents blood-to-brain transport. Here we label hundreds of proteins constituting the mouse blood plasma proteome, and upon their systemic administration, study the BBB with its physiological ligand. We find that plasma proteins readily permeate the healthy brain parenchyma, with transport maintained by BBB-specific transcriptional programmes. Unlike IgG antibody, plasma protein uptake diminishes in the aged brain, driven by an age-related shift in transport from ligand-specific receptor-mediated to non-specific caveolar transcytosis. This age-related shift occurs alongside a specific loss of pericyte coverage. Pharmacological inhibition of the age-upregulated phosphatase ALPL, a predicted negative regulator of transport, enhances brain uptake of therapeutically relevant transferrin, transferrin receptor antibody and plasma. These findings reveal the extent of physiological protein transcytosis to the healthy brain, a mechanism of widespread BBB dysfunction with age and a strategy for enhanced drug delivery.


Assuntos
Envelhecimento/metabolismo , Envelhecimento/patologia , Barreira Hematoencefálica/metabolismo , Transcitose , Fosfatase Alcalina/metabolismo , Animais , Anticorpos/metabolismo , Transporte Biológico , Proteínas Sanguíneas/administração & dosagem , Proteínas Sanguíneas/metabolismo , Proteínas Sanguíneas/farmacocinética , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Sistemas de Liberação de Medicamentos , Saúde , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plasma/metabolismo , Proteoma/administração & dosagem , Proteoma/metabolismo , Proteoma/farmacocinética , Receptores da Transferrina/imunologia , Transcrição Genética , Transferrina/metabolismo
9.
Life Sci ; 258: 118119, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32682915

RESUMO

Ceftriaxone (CTX) is a third-generation cephalosporin antibiotic that has broad-spectrum antimicrobial activity. This agent also has anti-inflammatory and antioxidant characteristics. In the current study, the effects of CTX against hepatorenal damages in a D-galactose (DGL) induced aging model were investigated. We used twenty-eight male mice which equally and randomly were separated into four groups as follows: Control, DGL group (treated with 500 mg/kg/day DGL orally for six weeks), DGL + CTX group (treated with 500 mg/kg/day DGL orally plus 200 mg/kg/day CTX intraperitoneally for six weeks), and CTX group (treated with 200 mg/kg/day CTX intraperitoneally for six weeks). The liver and kidney function indices such as serum creatinine, blood urine nitrogen, alanine aminotransferase, and aspartate aminotransferase were measured. Also, levels of malondialdehyde, catalase, and glutathione peroxidase in hepatic and renal tissues were evaluated. Moreover, the expression profiles of interleukin 1 beta and tumor necrosis factor alpha were assessed. The liver and kidney tissues were assessed for histopathological lesions. The results showed that aging induced by DGL leads to abnormalities in functional indices of the liver and kidneys. DGL also induced significant oxidative stress and inflammation, as well as histopathological lesions, in these organs. CTX improved functional indices, as well as the parameters of oxidative stress and inflammation, compared with the DGL-treated animals. These results were also confirmed by histological evaluations of the liver and kidneys. These data provide evidence for the therapeutic value of CTX in clinical practice for mitigating the hepatorenal damages of aging.


Assuntos
Envelhecimento/patologia , Ceftriaxona/uso terapêutico , Síndrome Hepatorrenal/tratamento farmacológico , Animais , Ceftriaxona/farmacologia , Galactose , Inflamação/patologia , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos
10.
Neurology ; 95(5): e532-e544, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32661099

RESUMO

OBJECTIVE: To investigate the association between ß-amyloid (Aß) load and postmortem structural network topology in decedents without dementia. METHODS: Fourteen decedents (mean age at death 72.6 ± 7.2 years) without known clinical diagnosis of neurodegenerative disease and meeting pathology criteria only for no or low Alzheimer disease (AD) pathologic change were selected from the Normal Aging Brain Collection Amsterdam database. In situ brain MRI included 3D T1-weighted images for anatomical registration and diffusion tensor imaging for probabilistic tractography with subsequent structural network construction. Network topologic measures of centrality (degree), integration (global efficiency), and segregation (clustering and local efficiency) were calculated. Tissue sections from 12 cortical regions were sampled and immunostained for Aß and hyperphosphorylated tau (p-tau), and histopathologic burden was determined. Linear mixed effect models were used to assess the relationship between Aß and p-tau load and network topologic measures. RESULTS: Aß was present in 79% of cases and predominantly consisted of diffuse plaques; p-tau was sparsely present. Linear mixed effect models showed independent negative associations between Aß load and global efficiency (ß = -0.83 × 10-3, p = 0.014), degree (ß = -0.47, p = 0.034), and clustering (ß = -0.55 × 10-2, p = 0.043). A positive association was present between Aß load and local efficiency (ß = 3.16 × 10-3, p = 0.035). Regionally, these results were significant in the posterior cingulate cortex (PCC) for degree (ß = -2.22, p < 0.001) and local efficiency (ß = 1.01 × 10-2, p = 0.014) and precuneus for clustering (ß = -0.91 × 10-2, p = 0.017). There was no relationship between p-tau and network topology. CONCLUSION: This study in deceased adults with AD-related pathologic change provides evidence for a relationship among early Aß accumulation, predominantly of the diffuse type, and structural network topology, specifically of the PCC and precuneus.


Assuntos
Envelhecimento/patologia , Peptídeos beta-Amiloides , Encéfalo/patologia , Rede Nervosa/patologia , Idoso , Idoso de 80 Anos ou mais , Encéfalo/fisiopatologia , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiopatologia , Redes Neurais de Computação
11.
PLoS Biol ; 18(6): e3000731, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32479501

RESUMO

The nuclear lamina protein lamin A/C is a key component of the nuclear envelope. Mutations in the lamin A/C gene (LMNA) are identified in patients with various types of laminopathy-containing diseases, which have features of accelerated aging and osteoporosis. However, the underlying mechanisms for laminopathy-associated osteoporosis remain largely unclear. Here, we provide evidence that loss of lamin A/C in skeletal muscles, but not osteoblast (OB)-lineage cells, results in not only muscle aging-like deficit but also trabecular bone loss, a feature of osteoporosis. The latter is due in large part to elevated bone resorption. Further cellular studies show an increase of osteoclast (OC) differentiation in cocultures of bone marrow macrophages/monocytes (BMMs) and OBs after treatment with the conditioned medium (CM) from lamin A/C-deficient muscle cells. Antibody array screening analysis of the CM proteins identifies interleukin (IL)-6, whose expression is markedly increased in lamin A/C-deficient muscles. Inhibition of IL-6 by its blocking antibody in BMM-OB cocultures diminishes the increase of osteoclastogenesis. Knockout (KO) of IL-6 in muscle lamin A/C-KO mice diminishes the deficits in trabecular bone mass but not muscle. Further mechanistic studies reveal an elevation of cellular senescence marked by senescence-associated beta-galactosidase (SA-ß-gal), p16Ink4a, and p53 in lamin A/C-deficient muscles and C2C12 muscle cells, and the p16Ink4a may induce senescence-associated secretory phenotype (SASP) and IL-6 expression. Taken together, these results suggest a critical role for skeletal muscle lamin A/C to prevent cellular senescence, IL-6 expression, hyperosteoclastogenesis, and trabecular bone loss, uncovering a pathological mechanism underlying the link between muscle aging/senescence and osteoporosis.


Assuntos
Envelhecimento/patologia , Lamina Tipo A/deficiência , Músculo Esquelético/patologia , Osteoporose/patologia , Animais , Anticorpos Bloqueadores/farmacologia , Fenômenos Biomecânicos , Reabsorção Óssea/complicações , Reabsorção Óssea/patologia , Osso Esponjoso/efeitos dos fármacos , Osso Esponjoso/patologia , Diferenciação Celular/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Interleucina-6/metabolismo , Camundongos Knockout , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia , Osteogênese/efeitos dos fármacos , Osteoporose/sangue , Fenótipo
12.
J Immunol ; 205(2): 313-320, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32493812

RESUMO

Aging impairs immunity to promote diseases, especially respiratory viral infections. The current COVID-19 pandemic, resulting from SARS-CoV-2, induces acute pneumonia, a phenotype that is alarmingly increased with aging. In this article, we review findings of how aging alters immunity to respiratory viral infections to identify age-impacted pathways common to several viral pathogens, permitting us to speculate about potential mechanisms of age-enhanced mortality to COVID-19. Aging generally leads to exaggerated innate immunity, particularly in the form of elevated neutrophil accumulation across murine and large animal studies of influenza infection. COVID-19 patients who succumb exhibit a 2-fold increase in neutrophilia, suggesting that exaggerated innate immunity contributes to age-enhanced mortality to SARS-CoV-2 infection. Further investigation in relevant experimental models will elucidate the mechanisms by which aging impacts respiratory viral infections, including SARS-CoV-2. Such investigation could identify therapies to reduce the suffering of the population at large, but especially among older people, infected with respiratory viruses.


Assuntos
Envelhecimento/patologia , Betacoronavirus/fisiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/patologia , Pneumonia Viral/imunologia , Pneumonia Viral/patologia , Infecções Respiratórias/virologia , Doenças Cardiovasculares/patologia , Doenças Cardiovasculares/virologia , Citocinas/imunologia , Humanos , Influenza Humana/imunologia , Influenza Humana/patologia , Pandemias , Infecções Respiratórias/patologia , Vírus da SARS/fisiologia
13.
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
14.
Am J Physiol Heart Circ Physiol ; 319(1): H222-H234, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32530752

RESUMO

Protection against increased vascular stiffness in young women is lost after menopause. However, little is known about vascular stiffness in older, premenopausal females, because most of the prior work has been conducted in rodents, which live for only 1-3 yr and do not go through menopause. The goal of the current investigation was to quantitate differences in stiffness down the aortic tree and the mechanisms mediating those differences in older, premenopausal (24 ± 0.7 yr) versus young adult (7 ± 0.7 yr) female nonhuman primates. Aortic stiffness (ß), calculated from direct and continuous measurements of aortic diameter and pressure in chronically instrumented, conscious macaque monkeys, increased 2.5-fold in the thoracic aorta and fivefold in the abdominal aorta in old premenopausal monkeys. The aortic histological mechanisms mediating increased vascular stiffness, i.e., collagen/elastin ratio, elastin, and collagen disarray, and the number of breaks in elastin and collagen fibers were greater in the old premenopausal versus young monkeys and greater in the abdominal versus the thoracic aorta and greatest in the iliac artery. In addition, more immature and less cross-linked fibers of collagen were found in the aortas of young females. Aortic stiffness increased in old premenopausal female monkeys, more so in the abdominal aorta than in the thoracic aorta. Histological mechanisms mediating the increased aortic stiffness were augmented in the old premenopausal females, greater in the abdominal versus the thoracic aorta, and greatest in the iliac artery.NEW & NOTEWORTHY This is the first study to examine vascular stiffness down the aortic tree in aging premenopausal females (24 ± 0.7 yr old), whereas prior work studied mainly rodents, which are short-lived and do not undergo menopause. Histological mechanisms mediating vascular stiffness in older premenopausal females increased progressively down the aortic tree, with greater increases in the abdominal aorta compared with the thoracic aorta and with the greatest increases and differences observed in the iliac artery.


Assuntos
Envelhecimento/patologia , Aorta/patologia , Rigidez Vascular , Animais , Aorta/crescimento & desenvolvimento , Aorta/metabolismo , Colágeno/metabolismo , Elastina/metabolismo , Feminino , Macaca fascicularis , Macaca mulatta
15.
J Vis Exp ; (159)2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32478750

RESUMO

Drosophila serves as a useful model for assessing synaptic structure and function associated with neurodegenerative diseases. While much work has focused on neuromuscular junctions (NMJs) in Drosophila larvae, assessing synaptic integrity in adult Drosophila has received much less attention. Here we provide a straightforward method for dissection of the dorsal longitudinal muscles (DLMs), which are required for flight ability. In addition to flight as a behavioral readout, this dissection allows for the both DLM synapses and muscle tissue to be amenable to structural analysis using fluorescently labeled antibodies for synaptic markers or proteins of interest. This protocol allows for the evaluation of the structural integrity of synapses in adult Drosophila during aging to model the progressive, age-dependent nature of most neurodegenerative diseases.


Assuntos
Envelhecimento/patologia , Drosophila melanogaster/fisiologia , Degeneração Neural/patologia , Sinapses/metabolismo , Esclerose Amiotrófica Lateral/patologia , Animais , Animais Geneticamente Modificados , Denervação , Dissecação , Congelamento , Humanos , Larva/metabolismo , Junção Neuromuscular/fisiologia , Coloração e Rotulagem , Tórax
16.
J Vis Exp ; (160)2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32568219

RESUMO

In a constantly aging population, the prevalence of neurodegenerative disorders is expected to rise. Understanding disease mechanisms is the key to find preventive and curative measures. The most effective way to achieve this is through direct examination of diseased and healthy brain tissue. The authors present a protocol to obtain, process, characterize and store good quality brain tissue donated by individuals registered in an antemortem brain donation program. The donation program includes a face-to-face empathic approach to people, a collection of complementary clinical, biological, social and lifestyle information and serial multi-dimensional assessments over time to track individual trajectories of normal aging and cognitive decline. Since many neurological diseases are asymmetrical, our brain bank offers a unique protocol for slicing fresh specimens. Brain sections of both hemispheres are alternately frozen (at -80 °C) or fixed in formalin; a fixed slice on one hemisphere corresponds to a frozen one on the other hemisphere. With this approach, a complete histological characterization of all frozen material can be obtained, and omics studies can be performed on histologically well-defined tissues from both hemispheres thus offering a more complete assessment of neurodegenerative disease mechanisms. Correct and definite diagnosis of these diseases can only be achieved by combining the clinical syndrome with the neuropathological evaluation, which often adds important etiological clues necessary to interpret the pathogenesis. This method can be time consuming, expensive and limited as it only covers a limited geographical area. Regardless of its limitations, the high degree of characterization it provides can be rewarding. Our ultimate goal is to establish the first Italian Brain Bank, all the while emphasizing the importance of neuropathologically verified epidemiological studies.


Assuntos
Envelhecimento , Encéfalo/citologia , Manejo de Espécimes/métodos , Bancos de Tecidos , Idoso , Envelhecimento/patologia , Encéfalo/patologia , Humanos , Doenças Neurodegenerativas/patologia
17.
Neurology ; 95(3): e256-e267, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32591471

RESUMO

OBJECTIVE: We studied interrelationships between CSF biomarkers and associations with APOE ε4 genotype, demographic variables, vascular variables, and clinical diagnosis in Olmsted County, Minnesota. METHODS: We included 774 Mayo Clinic Study of Aging participants (693 cognitively unimpaired [CU]; 71 with mild cognitive impairment [MCI]). CSF ß-amyloid 42 (Aß42), total tau (t-tau), and hyperphosphorylated tau (p-tau) were analyzed using Aß42 CSF, t-tau CSF, and p-tau (181P) CSF electrochemiluminescence immunoassays. Bivariate mixture models were used to evaluate latent classes. We used linear regression models to evaluate independent associations of APOE ε4, demographic factors, cardiovascular risk, and diagnosis with CSF biomarker levels. Results were weighted back to the Olmsted County population. RESULTS: Interrelationships between CSF Aß42 and p-tau/t-tau were consistent with 2 latent classes in the general population. In subgroup 1 (n = 547 [71%]), we found a strong positive correlation between Aß42 and p-tau (ρ = 0.81), while the correlation was much smaller in group 2 (ρ = 0.26, n = 227 [29%]). Group 2 was associated with older age, APOE ε4 genotype, a diagnosis of MCI, and elevated amyloid PET. Overall, APOE ε4 genotype and MCI were associated with Aß42, while age was associated with p-tau/t-tau. There were no associations with sex, education, or vascular risk. CONCLUSION: We hypothesize the population without dementia can be subdivided into participants with and without biological Alzheimer disease (AD) based on the combination of CSF Aß42 and p-tau/t-tau (represented also by the p-tau/t-tau/Aß42 ratio). In those without biological AD, common factors such as CSF dynamics may cause a positive correlation between CSF Aß42 and p-tau/t-tau, while AD leads to dissociation of these proteins.


Assuntos
Envelhecimento/líquido cefalorraquidiano , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico por imagem , Medicina Baseada em Evidências/métodos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/patologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Disfunção Cognitiva/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Minnesota/epidemiologia , Fragmentos de Peptídeos/líquido cefalorraquidiano , Tomografia por Emissão de Pósitrons/métodos , Punção Espinal/métodos , Proteínas tau/líquido cefalorraquidiano
18.
Proc Natl Acad Sci U S A ; 117(23): 13094-13104, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32434914

RESUMO

Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly. While the histopathology of the different disease stages is well characterized, the cause underlying the progression, from the early drusen stage to the advanced macular degeneration stage that leads to blindness, remains unknown. Here, we show that photoreceptors (PRs) of diseased individuals display increased expression of two key glycolytic genes, suggestive of a glucose shortage during disease. Mimicking aspects of this metabolic profile in PRs of wild-type mice by activation of the mammalian target of rapamycin complex 1 (mTORC1) caused early drusen-like pathologies, as well as advanced AMD-like pathologies. Mice with activated mTORC1 in PRs also displayed other early disease features, such as a delay in photoreceptor outer segment (POS) clearance and accumulation of lipofuscin in the retinal-pigmented epithelium (RPE) and of lipoproteins at the Bruch's membrane (BrM), as well as changes in complement accumulation. Interestingly, formation of drusen-like deposits was dependent on activation of mTORC1 in cones. Both major types of advanced AMD pathologies, including geographic atrophy (GA) and neovascular pathologies, were also seen. Finally, activated mTORC1 in PRs resulted in a threefold reduction in di-docosahexaenoic acid (DHA)-containing phospholipid species. Feeding mice a DHA-enriched diet alleviated most pathologies. The data recapitulate many aspects of the human disease, suggesting that metabolic adaptations in photoreceptors could contribute to disease progression in AMD. Identifying the changes downstream of mTORC1 that lead to advanced pathologies in mouse might present new opportunities to study the role of PRs in AMD pathogenesis.


Assuntos
Envelhecimento/patologia , Macula Lutea/patologia , Degeneração Macular/patologia , Células Fotorreceptoras Retinianas Cones/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Lâmina Basilar da Corioide/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Lipofuscina/metabolismo , Lipoproteínas/metabolismo , Macula Lutea/citologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Células Fotorreceptoras Retinianas Cones/metabolismo , Epitélio Pigmentado da Retina/metabolismo
19.
Proc Natl Acad Sci U S A ; 117(22): 12029-12040, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32404427

RESUMO

Hutchinson-Gilford progeria syndrome (HGPS) is a uniformly fatal condition that is especially prevalent in skin, cardiovascular, and musculoskeletal systems. A wide gap exists between our knowledge of the disease and a promising treatment or cure. The aim of this study was to first characterize the musculoskeletal phenotype of the homozygous G608G BAC-transgenic progeria mouse model, and to determine the phenotype changes of HGPS mice after a five-arm preclinical trial of different treatment combinations with lonafarnib, pravastatin, and zoledronic acid. Microcomputed tomography and CT-based rigidity analyses were performed to assess cortical and trabecular bone structure, density, and rigidity. Bones were loaded to failure with three-point bending to assess strength. Contrast-enhanced µCT imaging of mouse femurs was performed to measure glycosaminoglycan content, thickness, and volume of the femoral head articular cartilage. Advanced glycation end products were assessed with a fluorometric assay. The changes demonstrated in the cortical bone structure, rigidity, stiffness, and modulus of the HGPS G608G mouse model may increase the risk for bending and deformation, which could result in the skeletal dysplasia characteristic of HGPS. Cartilage abnormalities seen in this HGPS model resemble changes observed in the age-matched WT controls, including early loss of glycosaminoglycans, and decreased cartilage thickness and volume. Such changes might mimic prevalent degenerative joint diseases in the elderly. Lonafarnib monotherapy did not improve bone or cartilage parameters, but treatment combinations with pravastatin and zoledronic acid significantly improved bone structure and mechanical properties and cartilage structural parameters, which ameliorate the musculoskeletal phenotype of the disease.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Modelos Animais de Doenças , Lamina Tipo A/genética , Progéria , Envelhecimento/efeitos dos fármacos , Envelhecimento/patologia , Animais , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Cartilagem/efeitos dos fármacos , Cartilagem/patologia , Fêmur/efeitos dos fármacos , Fêmur/patologia , Glicosaminoglicanos/análise , Articulações/efeitos dos fármacos , Articulações/patologia , Lamina Tipo A/metabolismo , Camundongos , Camundongos Transgênicos , Mutação , Osteoartrite/tratamento farmacológico , Osteoartrite/patologia , Fenótipo , Piperidinas/uso terapêutico , Pravastatina/uso terapêutico , Progéria/tratamento farmacológico , Progéria/genética , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Piridinas/uso terapêutico , Microtomografia por Raio-X , Ácido Zoledrônico/uso terapêutico
20.
Nat Commun ; 11(1): 2484, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32424276

RESUMO

DNA damage contributes to brain aging and neurodegenerative diseases. However, the factors stimulating DNA repair to stave off functional decline remain obscure. We show that HDAC1 modulates OGG1-initated 8-oxoguanine (8-oxoG) repair in the brain. HDAC1-deficient mice display age-associated DNA damage accumulation and cognitive impairment. HDAC1 stimulates OGG1, a DNA glycosylase known to remove 8-oxoG lesions that are associated with transcriptional repression. HDAC1 deficiency causes impaired OGG1 activity, 8-oxoG accumulation at the promoters of genes critical for brain function, and transcriptional repression. Moreover, we observe elevated 8-oxoG along with reduced HDAC1 activity and downregulation of a similar gene set in the 5XFAD mouse model of Alzheimer's disease. Notably, pharmacological activation of HDAC1 alleviates the deleterious effects of 8-oxoG in aged wild-type and 5XFAD mice. Our work uncovers important roles for HDAC1 in 8-oxoG repair and highlights the therapeutic potential of HDAC1 activation to counter functional decline in brain aging and neurodegeneration.


Assuntos
Envelhecimento/patologia , Doença de Alzheimer/patologia , Encéfalo/patologia , Dano ao DNA , DNA Glicosilases/metabolismo , Histona Desacetilase 1/metabolismo , Estresse Oxidativo , Acetilação , Envelhecimento/genética , Doença de Alzheimer/complicações , Doença de Alzheimer/fisiopatologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Astrócitos/patologia , Sequência de Bases , Benzofenonas/farmacologia , Cognição/efeitos dos fármacos , Transtornos Cognitivos/complicações , Transtornos Cognitivos/patologia , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Ontologia Genética , Guanina/análogos & derivados , Guanina/metabolismo , Memória/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Regiões Promotoras Genéticas/genética
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