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2.
Nat Commun ; 15(1): 1073, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316771

RESUMO

Dietary restriction promotes resistance to surgical stress in multiple organisms. Counterintuitively, current medical protocols recommend short-term carbohydrate-rich drinks (carbohydrate loading) prior to surgery, part of a multimodal perioperative care pathway designed to enhance surgical recovery. Despite widespread clinical use, preclinical and mechanistic studies on carbohydrate loading in surgical contexts are lacking. Here we demonstrate in ad libitum-fed mice that liquid carbohydrate loading for one week drives reductions in solid food intake, while nearly doubling total caloric intake. Similarly, in humans, simple carbohydrate intake is inversely correlated with dietary protein intake. Carbohydrate loading-induced protein dilution increases expression of hepatic fibroblast growth factor 21 (FGF21) independent of caloric intake, resulting in protection in two models of surgical stress: renal and hepatic ischemia-reperfusion injury. The protection is consistent across male, female, and aged mice. In vivo, amino acid add-back or genetic FGF21 deletion blocks carbohydrate loading-mediated protection from ischemia-reperfusion injury. Finally, carbohydrate loading induction of FGF21 is associated with the induction of the canonical integrated stress response (ATF3/4, NF-kB), and oxidative metabolism (PPARγ). Together, these data support carbohydrate loading drinks prior to surgery and reveal an essential role of protein dilution via FGF21.


Assuntos
Dieta da Carga de Carboidratos , Fatores de Crescimento de Fibroblastos , Traumatismo por Reperfusão , Procedimentos Cirúrgicos Operatórios , Animais , Feminino , Humanos , Masculino , Camundongos , Carboidratos da Dieta/metabolismo , Proteínas na Dieta/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Fígado/cirurgia , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão/metabolismo
3.
Nat Aging ; 4(2): 261-274, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38200273

RESUMO

Epigenetic 'clocks' based on DNA methylation have emerged as the most robust and widely used aging biomarkers, but conventional methods for applying them are expensive and laborious. Here we develop tagmentation-based indexing for methylation sequencing (TIME-seq), a highly multiplexed and scalable method for low-cost epigenetic clocks. Using TIME-seq, we applied multi-tissue and tissue-specific epigenetic clocks in over 1,800 mouse DNA samples from eight tissue and cell types. We show that TIME-seq clocks are accurate and robust, enriched for polycomb repressive complex 2-regulated loci, and benchmark favorably against conventional methods despite being up to 100-fold less expensive. Using dietary treatments and gene therapy, we find that TIME-seq clocks reflect diverse interventions in multiple tissues. Finally, we develop an economical human blood clock (R > 0.96, median error = 3.39 years) in 1,056 demographically representative individuals. These methods will enable more efficient epigenetic clock measurement in larger-scale human and animal studies.


Assuntos
Metilação de DNA , Trabalho de Parto , Gravidez , Feminino , Humanos , Camundongos , Animais , Metilação de DNA/genética , Epigênese Genética , Envelhecimento/genética , Epigenômica/métodos
4.
Nat Commun ; 14(1): 8142, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38065964

RESUMO

To ameliorate or even prevent signatures of aging in ultimately humans, we here report the identification of a previously undescribed polyacetylene contained in the root of carrots (Daucus carota), hereafter named isofalcarintriol, which we reveal as potent promoter of longevity in the nematode C. elegans. We assign the absolute configuration of the compound as (3 S,8 R,9 R,E)-heptadeca-10-en-4,6-diyne-3,8,9-triol, and develop a modular asymmetric synthesis route for all E-isofalcarintriol stereoisomers. At the molecular level, isofalcarintriol affects cellular respiration in mammalian cells, C. elegans, and mice, and interacts with the α-subunit of the mitochondrial ATP synthase to promote mitochondrial biogenesis. Phenotypically, this also results in decreased mammalian cancer cell growth, as well as improved motility and stress resistance in C. elegans, paralleled by reduced protein accumulation in nematodal models of neurodegeneration. In addition, isofalcarintriol supplementation to both wild-type C57BL/6NRj mice on high-fat diet, and aged mice on chow diet results in improved glucose metabolism, increased exercise endurance, and attenuated parameters of frailty at an advanced age. Given these diverse effects on health parameters in both nematodes and mice, isofalcarintriol might become a promising mitohormesis-inducing compound to delay, ameliorate, or prevent aging-associated diseases in humans.


Assuntos
Caenorhabditis elegans , Daucus carota , Humanos , Animais , Camundongos , Caenorhabditis elegans/metabolismo , Mitocôndrias/metabolismo , Camundongos Endogâmicos C57BL , Envelhecimento , Longevidade , Poli-Inos/metabolismo , Mamíferos
5.
bioRxiv ; 2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37961405

RESUMO

Short-term preoperative methionine restriction (MetR) shows promise as a translatable strategy to modulate the body's response to surgical injury. Its application, however, to improve post-interventional vascular remodeling remains underexplored. Here, we find that MetR protects from arterial intimal hyperplasia in a focal stenosis model and adverse vascular remodeling after vein graft surgery. RNA sequencing reveals that MetR enhances the brown adipose tissue phenotype in arterial perivascular adipose tissue (PVAT) and induces it in venous PVAT. Specifically, PPAR-α was highly upregulated in PVAT-adipocytes. Furthermore, MetR dampens the post-operative pro-inflammatory response to surgery in PVAT-macrophages in vivo and in vitro . This study shows for the first time that the detrimental effects of dysfunctional PVAT on vascular remodeling can be reversed by MetR, and identifies pathways involved in browning of PVAT. Furthermore, we demonstrate the potential of short-term pre-operative MetR as a simple intervention to ameliorate vascular remodeling after vascular surgery.

6.
Br J Clin Pharmacol ; 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37675638

RESUMO

Preclinical models have been the backbone of translational research for more than a century. Rats and mice are critical models in the preliminary stages of drug testing, both for determining efficacy and ruling out potential human-relevant toxicities. Historically, most preclinical pharmacological studies have used young, relatively healthy, inbred male models in highly controlled environments. In the field of geriatric pharmacology, there is a growing focus on the importance of using more appropriate preclinical models both in the testing of therapeutics commonly used in older populations, and in the evaluation of potential geroprotective drug candidates. Here we provide a commentary on optimizing preclinical models of ageing for translation to clinical trials. We will discuss approaches to modelling clinically relevant contexts such as age, sex, genetic diversity, exposures and environment, as well as measures of clinically relevant outcomes such as frailty and healthspan. We will identify the strengths and limitations of these approaches and areas for improvement. We will also briefly cover new preclinical models that move beyond rodents. We hope this commentary will be a springboard for larger discussions on optimizing preclinical ageing models for testing therapeutics.

7.
Front Aging ; 4: 1172789, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37305228

RESUMO

With an increasing aging population, the burden of age-related diseases magnifies. To alleviate this burden, geroprotection has been an area of intense research focus with the development of pharmacological interventions that target lifespan and/or healthspan. However, there are often sex differences, with compounds mostly tested in male animals. Given the importance of considering both sexes in preclinical research, this neglects potential benefits for the female population, as interventions tested in both sexes often show clear sexual dimorphisms in their biological responses. To further understand the prevalence of sex differences in pharmacological geroprotective intervention studies, we performed a systematic review of the literature according to the PRISMA guidelines. Seventy-two studies met our inclusion criteria and were classified into one of five subclasses: FDA-repurposed drugs, novel small molecules, probiotics, traditional Chinese medicine, and antioxidants, vitamins, or other dietary supplements. Interventions were analyzed for their effects on median and maximal lifespan and healthspan markers, including frailty, muscle function and coordination, cognitive function and learning, metabolism, and cancer. With our systematic review, we found that twenty-two out of sixty-four compounds tested were able to prolong both lifespan and healthspan measures. Focusing on the use of female and male mice, and on comparing their outcomes, we found that 40% of studies only used male mice or did not clarify the sex. Notably, of the 36% of pharmacologic interventions that did use both male and female mice, 73% of these studies showed sex-specific outcomes on healthspan and/or lifespan. These data highlight the importance of studying both sexes in the search for geroprotectors, as the biology of aging is not the same in male and female mice. Systematic Review Registration: [website], identifier [registration number].

8.
JVS Vasc Sci ; 4: 100095, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36852171

RESUMO

Objective: Hydrogen sulfide is a proangiogenic gas produced primarily by the transsulfuration enzyme cystathionine-γ-lyase (CGL). CGL-dependent hydrogen sulfide production is required for neovascularization in models of peripheral arterial disease. However, the benefits of increasing endogenous CGL and its mechanism of action have not yet been elucidated. Methods: Male whole body CGL-overexpressing transgenic (CGLTg) mice and wild-type (WT) littermates (C57BL/6J) were subjected to the hindlimb ischemia model (age, 10-12 weeks). Functional recovery was assessed via the treadmill exercise endurance test. Leg perfusion was measured by laser Doppler imaging and vascular endothelial-cadherin immunostaining. To examine the angiogenic potential, aortic ring sprouting assay and postnatal mouse retinal vasculature development studies were performed. Finally, comparative metabolomics analysis, oxidized/reduced nicotinamide adenine dinucleotide (NAD+/NADH) analysis, and quantitative real-time polymerase chain reaction were performed on CGLWT and CGLTg gastrocnemius muscle. Results: The restoration of blood flow occurred more rapidly in CGLTg mice. Compared with the CGLWT mice, the median ± standard deviation running distance and time were increased for the CGLTg mice after femoral artery ligation (159 ± 53 m vs 291 ± 74 m [P < .005] and 17 ± 4 minutes vs 27 ± 5 minutes [P < .05], respectively). Consistently, in the CGLTg ischemic gastrocnemius muscle, the capillary density was increased fourfold (0.05 ± 0.02 vs 0.20 ± 0.12; P < .005). Ex vivo, the endothelial cell (EC) sprouting length was increased in aorta isolated from CGLTg mice, especially when cultured in VEGFA (vascular endothelial growth factor A)-only media (63 ± 2 pixels vs 146 ± 52 pixels; P < .05). Metabolomics analysis demonstrated a higher level of niacinamide, a precursor of NAD+/NADH in the muscle of CGLTg mice (61.4 × 106 ± 5.9 × 106 vs 72.4 ± 7.7 × 106 area under the curve; P < .05). Similarly, the NAD+ salvage pathway gene expression was increased in CGLTg gastrocnemius muscle. Finally, CGL overexpression or supplementation with the NAD+ precursor nicotinamide mononucleotide improved EC migration in vitro (wound closure: control, 35% ± 9%; CGL, 55% ± 11%; nicotinamide mononucleotide, 42% ± 13%; P < .05). Conclusions: Our results have demonstrated that CGL overexpression improves the neovascularization of skeletal muscle on hindlimb ischemia. These effects correlated with changes in the NAD pathway, which improved EC migration.

10.
Cell ; 186(2): 305-326.e27, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36638792

RESUMO

All living things experience an increase in entropy, manifested as a loss of genetic and epigenetic information. In yeast, epigenetic information is lost over time due to the relocalization of chromatin-modifying proteins to DNA breaks, causing cells to lose their identity, a hallmark of yeast aging. Using a system called "ICE" (inducible changes to the epigenome), we find that the act of faithful DNA repair advances aging at physiological, cognitive, and molecular levels, including erosion of the epigenetic landscape, cellular exdifferentiation, senescence, and advancement of the DNA methylation clock, which can be reversed by OSK-mediated rejuvenation. These data are consistent with the information theory of aging, which states that a loss of epigenetic information is a reversible cause of aging.


Assuntos
Envelhecimento , Epigênese Genética , Animais , Envelhecimento/genética , Metilação de DNA , Epigenoma , Mamíferos/genética , Nucleoproteínas , Saccharomyces cerevisiae/genética
11.
Palliat Med ; 37(2): 235-243, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36461707

RESUMO

BACKGROUND: The need for end-of-life care in the community increased significantly during the COVID-19 pandemic. Primary care services, including general practitioners and community nurses, had a critical role in providing such care, rapidly changing their working practices to meet demand. Little is known about primary care responses to a major change in place of care towards the end of life, or the implications for future end-of-life care services. AIM: To gather general practitioner and community nurse perspectives on factors that facilitated community end-of-life care during the COVID-19 pandemic, and to use this to develop recommendations to improve future delivery of end-of-life care. DESIGN: Qualitative interview study with thematic analysis, followed by refinement of themes and recommendations in consultation with an expert advisory group. PARTICIPANTS: General practitioners (n = 8) and community nurses (n = 17) working in primary care in the UK. RESULTS: General practitioner and community nurse perspectives on factors critical to sustaining community end-of-life care were identified under three themes: (1) partnership working is key, (2) care planning for end-of-life needs improvement, and (3) importance of the physical presence of primary care professionals. Drawing on participants' experiences and behaviour change theory, recommendations are proposed to improve end-of-life care in primary care. CONCLUSIONS: To sustain and embed positive change, an increased policy focus on primary care in end-of-life care is required. Targeted interventions developed during COVID-19, including online team meetings and education, new prescribing systems and unified guidance, could increase capacity and capability of the primary care workforce to deliver community end-of-life care.


Assuntos
COVID-19 , Assistência Terminal , Humanos , Cuidados Paliativos , Pandemias , Pesquisa Qualitativa , Atenção Primária à Saúde
12.
Front Nutr ; 9: 951000, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466423

RESUMO

Fasting provokes fundamental changes in the activation of metabolic and signaling pathways leading to longer and healthier lifespans in animal models. Although the involvement of different metabolites in fueling human fasting metabolism is well known, the contribution of tissues and organs to their supply remains partly unclear. Also, changes in organ volume and composition remain relatively unexplored. Thus, processes involved in remodeling tissues during fasting and food reintroduction need to be better understood. Therefore, this study will apply state-of-the-art techniques to investigate the effects of long-term fasting (LF) and food reintroduction in humans by a multi-systemic approach focusing on changes in body composition, organ and tissue volume, lipid transport and storage, sources of protein utilization, blood metabolites, and gut microbiome profiles in a single cohort. This is a prospective, single-arm, monocentric trial. One hundred subjects will be recruited and undergo 9 ± 3 day-long fasting periods (250 kcal/day). We will assess changes in the composition of organs, bones and blood lipid profiles before and after fasting, as well as high-density lipoprotein (HDL) transport and storage, untargeted metabolomics of peripheral blood mononuclear cells (PBMCs), protein persulfidation and shotgun metagenomics of the gut microbiome. The first 32 subjects, fasting for 12 days, will be examined in more detail by magnetic resonance imaging (MRI) and spectroscopy to provide quantitative information on changes in organ volume and function, followed by an additional follow-up examination after 1 and 4 months. The study protocol was approved by the ethics board of the State Medical Chamber of Baden-Württemberg on 26.07.2021 and registered at ClinicalTrials.gov (NCT05031598). The results will be disseminated through peer-reviewed publications, international conferences and social media. Clinical trial registration: [ClinicalTrials.gov], identifier [NCT05031598].

13.
BMC Palliat Care ; 21(1): 155, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36064662

RESUMO

BACKGROUND: The provision of palliative care is increasing, with many people dying in community-based settings. It is essential that communication is effective if and when patients transition from hospice to community palliative care. Past research has indicated that communication issues are prevalent during hospital discharges, but little is known about hospice discharges. METHODS: An explanatory sequential mixed methods study consisting of a retrospective review of hospice discharge letters, followed by hospice focus groups, to explore patterns in communication of palliative care needs of discharged patients and describe why these patients were being discharged. Discharge letters were extracted for key content information using a standardised form. Letters were then examined for language patterns using a linguistic methodology termed corpus linguistics. Thematic analysis was used to analyse the focus group transcripts. Findings were triangulated to develop an explanatory understanding of discharge communication from hospice care. RESULTS: We sampled 250 discharge letters from five UK hospices whereby patients had been discharged to primary care. Twenty-five staff took part in focus groups. The main reasons for discharge extracted from the letters were symptoms "managed/resolved" (75.2%), and/or the "patient wishes to die/for care at home" (37.2%). Most patients had some form of physical needs documented on the letters (98.4%) but spiritual needs were rarely documented (2.4%). Psychological/emotional needs and social needs were documented in 46.4 and 35.6% of letters respectively. There was sometimes ambiguity in "who" will be following up "what" in the discharge letters, and whether described patients' needs were resolved or ongoing for managing in the community setting. The extent to which patients received a copy of their discharge letter varied. Focus groups conveyed a lack of consensus on what constitutes "complexity" and "complex pain". CONCLUSIONS: The content and structure of discharge letters varied between hospices, although generally focused on physical needs. Our study provides insights into patterns associated with those discharged from hospice, and how policy and guidance in this area may be improved, such as greater consistency of sharing letters with patients. A patient-centred set of hospice-specific discharge letter principles could help improve future practice.


Assuntos
Cuidados Paliativos na Terminalidade da Vida , Hospitais para Doentes Terminais , Comunicação , Humanos , Cuidados Paliativos , Alta do Paciente
14.
Cell Rep ; 40(7): 111187, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35977507

RESUMO

Dietary protein restriction (PR) has rapid effects on metabolism including improved glucose and lipid homeostasis, via multiple mechanisms. Here, we investigate responses of fecal microbiome, hepatic transcriptome, and hepatic metabolome to six diets with protein from 18% to 0% of energy in mice. PR alters fecal microbial composition, but metabolic effects are not transferable via fecal transplantation. Hepatic transcriptome and metabolome are significantly altered in diets with lower than 10% energy from protein. Changes upon PR correlate with calorie restriction but with a larger magnitude and specific changes in amino acid (AA) metabolism. PR increases steady-state aspartate, serine, and glutamate and decreases glucose and gluconeogenic intermediates. 13C6 glucose and glycerol tracing reveal increased fractional enrichment in aspartate, serine, and glutamate. Changes remain intact in hepatic ATF4 knockout mice. Together, this demonstrates an ATF4-independent shift in gluconeogenic substrate utilization toward specific AAs, with compensation from glycerol to promote a protein-sparing response.


Assuntos
Glucose , Glicerol , Animais , Ácido Aspártico/metabolismo , Proteínas na Dieta/metabolismo , Gluconeogênese , Glucose/metabolismo , Ácido Glutâmico/metabolismo , Glicerol/metabolismo , Fígado/metabolismo , Camundongos , Serina/metabolismo
15.
NPJ Aging ; 8(1): 8, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35927269

RESUMO

Skeletal muscle adapts to different exercise training modalities with age; however, the impact of both variables at the systemic and tissue levels is not fully understood. Here, adult and old C57BL/6 male mice were assigned to one of three groups: sedentary, daily high-intensity intermittent training (HIIT), or moderate intensity continuous training (MICT) for 4 weeks, compatible with the older group's exercise capacity. Improvements in body composition, fasting blood glucose, and muscle strength were mostly observed in the MICT old group, while effects of HIIT training in adult and old animals was less clear. Skeletal muscle exhibited structural and functional adaptations to exercise training, as revealed by electron microscopy, OXPHOS assays, respirometry, and muscle protein biomarkers. Transcriptomics analysis of gastrocnemius muscle combined with liver and serum metabolomics unveiled an age-dependent metabolic remodeling in response to exercise training. These results support a tailored exercise prescription approach aimed at improving health and ameliorating age-associated loss of muscle strength and function in the elderly.

16.
Cell Rep ; 39(7): 110824, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35584673

RESUMO

The tuberous sclerosis complex (TSC) 1 and 2 proteins associate with TBC1D7 to form the TSC complex, which is an essential suppressor of mTOR complex 1 (mTORC1), a ubiquitous driver of cell and tissue growth. Loss-of-function mutations in TSC1 or TSC2, but not TBC1D7, give rise to TSC, a pleiotropic disorder with aberrant activation of mTORC1 in various tissues. Here, we characterize mice with genetic deletion of Tbc1d7, which are viable with normal growth and development. Consistent with partial loss of function of the TSC complex, Tbc1d7 knockout (KO) mice display variable increases in tissue mTORC1 signaling with increased muscle fiber size but with strength and motor defects. Their most pronounced phenotype is brain overgrowth due to thickening of the cerebral cortex, with enhanced neuron-intrinsic mTORC1 signaling and growth. Thus, TBC1D7 is required for full TSC complex function in tissues, and the brain is particularly sensitive to its growth-suppressing activities.


Assuntos
Encéfalo , Peptídeos e Proteínas de Sinalização Intracelular , Alvo Mecanístico do Complexo 1 de Rapamicina , Neurônios , Proteína 1 do Complexo Esclerose Tuberosa , Esclerose Tuberosa , Proteínas Supressoras de Tumor , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Camundongos Knockout , Neurônios/citologia , Neurônios/metabolismo , Esclerose Tuberosa/metabolismo , Esclerose Tuberosa/patologia , Proteína 1 do Complexo Esclerose Tuberosa/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
17.
Front Nutr ; 9: 839341, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433789

RESUMO

There is increasing interest in utilizing short-term dietary interventions in the contexts of cancer, surgical stress and metabolic disease. These short-term diets may be more feasible than extended interventions and may be designed to complement existing therapies. In particular, the high-fat, low-carbohydrate ketogenic diet (KD), traditionally used to treat epilepsy, has gained popularity as a potential strategy for weight loss and improved metabolic health. In mice, long-term KD improves insulin sensitivity and may extend lifespan and healthspan. Dietary protein restriction (PR) causes increased energy expenditure, weight loss and improved glucose homeostasis. Since KD is inherently a low-protein diet (10% of calories from protein vs. >18% in control diet), here we evaluated the potential for mechanistic overlap between PR and KD via activation of a PR response. Mice were fed control, protein-free (PF), or one of four ketogenic diets with varying protein content for 8 days. PF and KD both decreased body weight, fat mass, and liver weights, and reduced fasting glucose and insulin levels, compared to mice fed the control diet. However, PF-fed animals had significantly improved insulin tolerance compared to KD. Furthermore, contrary to the PF-fed mice, mice fed ketogenic diets containing more than 5% of energy from protein did not increase hepatic Fgf21 or brown adipose Ucp1 expression. Interestingly, mice fed KD lacking protein demonstrated greater elevations in hepatic Fgf21 than mice fed a low-fat PF diet. To further elucidate potential mechanistic differences between PF and KD and the interplay between dietary protein and carbohydrate restriction, we conducted RNA-seq analysis on livers from mice fed each of the six diets and identified distinct gene sets which respond to dietary protein content, dietary fat content, and ketogenesis. We conclude that KD with 10% of energy from protein does not induce a protein restriction response, and that the overlapping metabolic benefits of KD and PF diets may occur via distinct underlying mechanisms.

18.
Nutrients ; 14(7)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35406143

RESUMO

Radiation therapy damages and depletes total bone marrow (BM) cellularity, compromising safety and limiting effective dosing. Aging also strains total BM and BM hematopoietic stem and progenitor cell (HSPC) renewal and function, resulting in multi-system defects. Interventions that preserve BM and BM HSPC homeostasis thus have potential clinical significance. Here, we report that 50% calorie restriction (CR) for 7-days or fasting for 3-days prior to irradiation improved mouse BM regrowth in the days and weeks post irradiation. Specifically, one week of 50% CR ameliorated loss of total BM cellularity post irradiation compared to ad libitum-fed controls. CR-mediated BM protection was abrogated by dietary sulfur amino acid (i.e., cysteine, methionine) supplementation or pharmacological inhibition of sulfur amino acid metabolizing and hydrogen sulfide (H2S) producing enzymes. Up to 2-fold increased proliferative capacity of ex vivo-irradiated BM isolated from food restricted mice relative to control mice indicates cell autonomy of the protective effect. Pretreatment with H2S in vitro was sufficient to preserve proliferative capacity by over 50% compared to non-treated cells in ex vivo-irradiated BM and BM HSPCs. The exogenous addition of H2S inhibited Ten eleven translocation 2 (TET2) activity in vitro, thus providing a potential mechanism of action. Short-term CR or fasting therefore offers BM radioprotection and promotes regrowth in part via altered sulfur amino acid metabolism and H2S generation, with translational implications for radiation treatment and aging.


Assuntos
Sulfeto de Hidrogênio , Lesões por Radiação , Animais , Medula Óssea/metabolismo , Restrição Calórica , Suplementos Nutricionais , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Metionina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Radiação Ionizante
19.
J Gerontol A Biol Sci Med Sci ; 77(11): 2177-2180, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-35172335

RESUMO

Five years ago, the National Institute of Health (NIH) introduced a mandate to revolutionize the way sex as a biological variable (SABV) is considered in NIH-funded preclinical research. Given the known effects of sex on aging physiology, pathology, treatment response, and the effectiveness of interventions it is particularly important that SABV be considered in basic biology of aging research. Five years after this mandate, a significant amount of published work funded by the National Institute on Aging (NIA) is still not including mice of both sexes and/or not considering sex differences or comparisons in preclinical studies. Here we review a cross-section of recently published NIA-funded research to determine adherence to this mandate. We discuss the state of the preclinical aging field in terms of SABV and suggest strategies for improving adherence to the NIH mandate. It is imperative that we consider SABV and include males and females in all aspects of aging biology research to improve health outcomes for all.


Assuntos
Pesquisa Biomédica , Feminino , Masculino , Animais , Camundongos , Fatores Sexuais , Gerociência , Caracteres Sexuais , Envelhecimento
20.
Front Cardiovasc Med ; 9: 1096887, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36741836

RESUMO

Background: Aging is associated with increased levels of reactive oxygen species and inflammation that disrupt proteostasis and mitochondrial function and leads to organism-wide frailty later in life. ARA290 (cibinetide), an 11-aa non-hematopoietic peptide sequence within the cardioprotective domain of erythropoietin, mediates tissue protection by reducing inflammation and fibrosis. Age-associated cardiac inflammation is linked to structural and functional changes in the heart, including mitochondrial dysfunction, impaired proteostasis, hypertrophic cardiac remodeling, and contractile dysfunction. Can ARA290 ameliorate these age-associated cardiac changes and the severity of frailty in advanced age? Methods: We conducted an integrated longitudinal (n = 48) and cross-sectional (n = 144) 15 months randomized controlled trial in which 18-month-old Fischer 344 x Brown Norway rats were randomly assigned to either receive chronic ARA290 treatment or saline. Serial echocardiography, tail blood pressure and body weight were evaluated repeatedly at 4-month intervals. A frailty index was calculated at the final timepoint (33 months of age). Tissues were harvested at 4-month intervals to define inflammatory markers and left ventricular tissue remodeling. Mitochondrial and myocardial cell health was assessed in isolated left ventricular myocytes. Kaplan-Meier survival curves were established. Mixed ANOVA tests and linear mixed regression analysis were employed to determine the effects of age, treatment, and age-treatment interactions. Results: Chronic ARA290 treatment mitigated age-related increases in the cardiac non-myocyte to myocyte ratio, infiltrating leukocytes and monocytes, pro-inflammatory cytokines, total NF-κB, and p-NF-κB. Additionally, ARA290 treatment enhanced cardiomyocyte autophagy flux and reduced cellular accumulation of lipofuscin. The cardiomyocyte mitochondrial permeability transition pore response to oxidant stress was desensitized following chronic ARA290 treatment. Concurrently, ARA290 significantly blunted the age-associated elevation in blood pressure and preserved the LV ejection fraction. Finally, ARA290 preserved body weight and significantly reduced other markers of organism-wide frailty at the end of life. Conclusion: Administration of ARA290 reduces cell and tissue inflammation, mitigates structural and functional changes within the cardiovascular system leading to amelioration of frailty and preserved healthspan.

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