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1.
bioRxiv ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39005372

RESUMO

Dietary restriction of the sulfur-containing amino acids methionine and cysteine (SAAR) improves body composition, enhances insulin sensitivity, and extends lifespan; benefits seen also with endurance exercise. Yet, the impact of SAAR on skeletal muscle remains largely unexplored. Here we demonstrate that one week of SAAR in sedentary, young, male mice increases endurance exercise capacity. Indirect calorimetry showed that SAAR increased lipid oxidation at rest and delayed the onset of carbohydrate utilization during exercise. Transcriptomic analysis revealed increased expression of genes involved in fatty acid catabolism especially in glycolytic muscle following SAAR. These findings were functionally supported by increased fatty acid circulatory turnover flux and muscle ß-oxidation. Reducing lipid uptake from circulation through endothelial cell (EC)-specific CD36 deletion attenuated the running phenotype. Mechanistically, VEGF-signaling inhibition prevented exercise increases following SAAR, without affecting angiogenesis, implicating noncanonical VEGF signaling and EC CD36-dependent fatty acid transport in regulating exercise capacity by influencing muscle substrate availability.

2.
bioRxiv ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38979132

RESUMO

Nicotinamide adenine dinucleotide (NAD) is essential for many enzymatic reactions, including those involved in energy metabolism, DNA repair and the activity of sirtuins, a family of defensive deacylases. During aging, levels of NAD + can decrease by up to 50% in some tissues, the repletion of which provides a range of health benefits in both mice and humans. Whether or not the NAD + precursor nicotinamide mononucleotide (NMN) extends lifespan in mammals is not known. Here we investigate the effect of long-term administration of NMN on the health, cancer burden, frailty and lifespan of male and female mice. Without increasing tumor counts or severity in any tissue, NMN treatment of males and females increased activity, maintained more youthful gene expression patterns, and reduced overall frailty. Reduced frailty with NMN treatment was associated with increases in levels of Anerotruncus colihominis, a gut bacterium associated with lower inflammation in mice and increased longevity in humans. NMN slowed the accumulation of adipose tissue later in life and improved metabolic health in male but not female mice, while in females but not males, NMN increased median lifespan by 8.5%, possible due to sex-specific effects of NMN on NAD + metabolism. Together, these data show that chronic NMN treatment delays frailty, alters the microbiome, improves male metabolic health, and increases female mouse lifespan, without increasing cancer burden. These results highlight the potential of NAD + boosters for treating age-related conditions and the importance of using both sexes for interventional lifespan studies.

3.
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 Alimentares/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Fígado/cirurgia , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão/metabolismo
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.

9.
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
10.
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
11.
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
12.
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
13.
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.

14.
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.

15.
Nutrients ; 13(11)2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34836280

RESUMO

(1) Background: Vascular surgery operations are hampered by high failure rates and frequent occurrence of peri-operative cardiovascular complications. In pre-clinical studies, pre-operative restriction of proteins and/or calories (PCR) has been shown to limit ischemia-reperfusion damage, slow intimal hyperplasia, and improve metabolic fitness. However, whether these dietary regimens are feasible and safe in the vascular surgery patient population remains unknown. (2) Methods: We performed a randomized controlled trial in patients scheduled for any elective open vascular procedure. Participants were randomized in a 3:2 ratio to either four days of outpatient pre-operative PCR (30% calorie, 70% protein restriction) or their regular ad-libitum diet. Blood was drawn at baseline, pre-operative, and post-operative day 1 timepoints. A leukocyte subset flow cytometry panel was performed at these timepoints. Subcutaneous/perivascular adipose tissue was sampled and analyzed. Follow-up was one year post-op. (3) Results: 19 patients were enrolled, of whom 11 completed the study. No diet-related reasons for non-completion were reported, and there was no intervention group crossover. The PCR diet induced weight loss and BMI decrease without malnutrition. Insulin sensitivity was improved after four days of PCR (p = 0.05). Between diet groups, there were similar rates of re-intervention, wound infection, and cardiovascular complications. Leukocyte populations were maintained after four days of PCR. (4) Conclusions: Pre-operative PCR is safe and feasible in elective vascular surgery patients.


Assuntos
Restrição Calórica/métodos , Proteínas/administração & dosagem , Procedimentos Cirúrgicos Vasculares/métodos , Idoso , Citocinas , Dieta , Dietoterapia , Ingestão de Energia , Exercício Físico , Feminino , Glucose , Homeostase , Humanos , Imunidade , Masculino , Pessoa de Meia-Idade , Redução de Peso
16.
Front Cardiovasc Med ; 8: 750926, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34760947

RESUMO

Objective: Hydrogen sulfide (H2S) is a gaseous signaling molecule and redox factor important for cardiovascular function. Deficiencies in its production or bioavailability are implicated in atherosclerotic disease. However, it is unknown if circulating H2S levels differ between vasculopaths and healthy individuals, and if so, whether H2S measurements can be used to predict surgical outcomes. Here, we examined: (1) Plasma H2S levels in patients undergoing vascular surgery and compared these to healthy controls, and (2) the association between H2S levels and mortality in a cohort of patients undergoing surgical revascularization. Methods: One hundred and fifteen patients undergoing carotid endarterectomy, open lower extremity revascularization or lower leg amputation were enrolled at a single institution. Peripheral blood was also collected from a matched control cohort of 20 patients without peripheral or coronary artery disease. Plasma H2S production capacity and sulfide concentration were measured using the lead acetate and monobromobimane methods, respectively. Results: Plasma H2S production capacity and plasma sulfide concentrations were reduced in patients with PAD (p < 0.001, p = 0.013, respectively). Patients that underwent surgical revascularization were divided into high vs. low H2S production capacity groups by median split. Patients in the low H2S production group had increased probability of mortality (p = 0.003). This association was robust to correction for potentially confounding variables using Cox proportional hazard models. Conclusion: Circulating H2S levels were lower in patients with atherosclerotic disease. Patients undergoing surgical revascularization with lower H2S production capacity, but not sulfide concentrations, had increased probability of mortality within 36 months post-surgery. This work provides insight on the role H2S plays as a diagnostic and potential therapeutic for cardiovascular disease.

17.
Cell Chem Biol ; 28(12): 1669-1678.e5, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34166610

RESUMO

Hydrogen sulfide (H2S) is a gasotransmitter with broad physiological activities, including protecting cells against stress, but little is known about the regulation of cellular H2S homeostasis. We have performed a high-content small-molecule screen and identified genotoxic agents, including cancer chemotherapy drugs, as activators of intracellular H2S levels. DNA damage-induced H2S in vitro and in vivo. Mechanistically, DNA damage elevated autophagy and upregulated H2S-generating enzyme CGL; chemical or genetic disruption of autophagy or CGL impaired H2S induction. Importantly, exogenous H2S partially rescued autophagy-deficient cells from genotoxic stress. Furthermore, stressors that are not primarily genotoxic (growth factor depletion and mitochondrial uncoupler FCCP) increased intracellular H2S in an autophagy-dependent manner. Our findings highlight the role of autophagy in H2S production and suggest that H2S generation may be a common adaptive response to DNA damage and other stressors.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Sulfeto de Hidrogênio/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Antineoplásicos/química , Dano ao DNA , Células HeLa , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Bibliotecas de Moléculas Pequenas/química
18.
Palliat Med ; 35(4): 793-798, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33726608

RESUMO

BACKGROUND: The active involvement of patients and the public in the design and conduct of research (Patient and Public Involvement) is important to add relevance and context. There are particular considerations for involving children and young people in research in potentially sensitive and emotional subject areas such as palliative care. AIM: To evaluate the experiences of young people of Patient and Public Involvement for a paediatric palliative care research study. DESIGN: Anonymous written feedback was collected from group members about their experiences of Patient and Public Involvement in a paediatric palliative care research study. An inductive thematic analysis of the feedback was conducted using NVivo. SETTING / PARTICIPANTS: Young people aged 12-22 years who were members of existing advisory groups at a children's hospital, hospice and the clinical research network in the West Midlands, UK. RESULTS: Feedback was provided by 30 young people at three meetings, held between December 2016 and February 2017. Three themes emerged: (1) Involvement: Young people have a desire to be involved in palliative care research, and recognise the importance of the subject area.(2) Impact: Researchers should demonstrate the impact of the involvement work on the research, by regularly providing feedback. (3) Learning: Opportunities to learn both about the topic and about research more widely were valued. CONCLUSIONS: Young people want to be involved in palliative care research, and recognise its importance. A continuous relationship with the researcher throughout the study, with clear demonstration of the impact that their input has on the research plans, are important.


Assuntos
Cuidados Paliativos na Terminalidade da Vida , Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Adolescente , Adulto , Criança , Humanos , Cuidados Paliativos , Projetos de Pesquisa , Adulto Jovem
19.
J Am Heart Assoc ; 9(22): e016391, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33146045

RESUMO

Background Failure rates after revascularization surgery remain high, both in vein grafts (VG) and arterial interventions. One promising approach to improve outcomes is endogenous upregulation of the gaseous transmitter-molecule hydrogen sulfide, via short-term dietary restriction. However, strict patient compliance stands as a potential translational barrier in the vascular surgery patient population. Here we present a new therapeutic approach, via a locally applicable gel containing the hydrogen sulfide releasing prodrug (GYY), to both mitigate graft failure and improve arterial remodeling. Methods and Results All experiments were performed on C57BL/6 (male, 12 weeks old) mice. VG surgery was performed by grafting a donor-mouse cava vein into the right common carotid artery of a recipient via an end-to-end anastomosis. In separate experiments arterial intimal hyperplasia was assayed via a right common carotid artery focal stenosis model. All mice were harvested at postoperative day 28 and artery/graft was processed for histology. Efficacy of hydrogen sulfide was first tested via GYY supplementation of drinking water either 1 week before VG surgery (pre-GYY) or starting immediately postoperatively (post-GYY). Pre-GYY mice had a 36.5% decrease in intimal/media+adventitia area ratio compared with controls. GYY in a 40% Pluronic gel (or vehicle) locally applied to the graft/artery had decreased intimal/media area ratios (right common carotid artery) and improved vessel diameters. GYY-geltreated VG had larger diameters at both postoperative days 14 and 28, and a 56.7% reduction in intimal/media+adventitia area ratios. Intimal vascular smooth muscle cell migration was decreased 30.6% after GYY gel treatment, which was reproduced in vitro. Conclusions Local gel-based treatment with the hydrogen sulfide-donor GYY stands as a translatable therapy to improve VG durability and arterial remodeling after injury.


Assuntos
Gasotransmissores/uso terapêutico , Sulfeto de Hidrogênio/uso terapêutico , Neointima/patologia , Neointima/prevenção & controle , Enxerto Vascular/efeitos adversos , Remodelação Vascular , Anastomose Cirúrgica , Animais , Artéria Carótida Primitiva/cirurgia , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neointima/etiologia , Veias Cavas/transplante
20.
Cell Metab ; 32(2): 203-214.e4, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32413333

RESUMO

Obesity is a top public health concern, and a molecule that safely treats obesity is urgently needed. Disulfiram (known commercially as Antabuse), an FDA-approved treatment for chronic alcohol addiction, exhibits anti-inflammatory properties and helps protect against certain types of cancer. Here, we show that in mice disulfiram treatment prevented body weight gain and abrogated the adverse impact of an obesogenic diet on insulin responsiveness while mitigating liver steatosis and pancreatic islet hypertrophy. Additionally, disulfiram treatment reversed established diet-induced obesity and metabolic dysfunctions in middle-aged mice. Reductions in feeding efficiency and increases in energy expenditure were associated with body weight regulation in response to long-term disulfiram treatment. Loss of fat tissue and an increase in liver fenestrations were also observed in rats on disulfiram. Given the potent anti-obesogenic effects in rodents, repurposing disulfiram in the clinic could represent a new strategy to treat obesity and its metabolic comorbidities.


Assuntos
Fármacos Antiobesidade/farmacologia , Peso Corporal/efeitos dos fármacos , Dissulfiram/farmacologia , Obesidade/tratamento farmacológico , Animais , Dieta/efeitos adversos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/induzido quimicamente , Obesidade/metabolismo , Ratos , Ratos Sprague-Dawley
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