Brown adipose tissue (BAT) contributes to cardiometabolic health by taking up glucose and lipids for oxidation, a process that displays a strong diurnal rhythm. While aging has been shown to reduce... Show moreBrown adipose tissue (BAT) contributes to cardiometabolic health by taking up glucose and lipids for oxidation, a process that displays a strong diurnal rhythm. While aging has been shown to reduce thermogenic characteristics of BAT, it is as yet unknown whether this reduction is specific to the time of day. Therefore, we assessed whole-body and BAT energy metabolism in young and middle-aged male and female C57BL/6J mice and studied the consequences for lipid metabolism in humanized APOE*3-Leiden.CETP mice (also on a C57BL/6J background). We demonstrate that in middle-aged versus young mice body temperature is lower in both male and female mice, while uptake of triglyceride (TG)-derived fatty acids (FAs) by BAT, reflecting metabolic activity, is attenuated at its peak at the onset of the dark (wakeful) phase in female mice. This coincided with delayed plasma clearance of TG-rich lipoproteins and TG-depleted lipoprotein core remnants, and elevated plasma TGs at the same time point. Furthermore, middle-aged female mice showed increased adiposity, accompanied by lipid accumulation, increased expression of genes involved in lipogenesis, and reduced expression of genes involved in fat oxidation and the intracellular clock machinery in BAT. Peak abundance of lipoprotein lipase (LPL), a crucial regulator of FA uptake, was attenuated in BAT. Our findings suggest that LPL is a potential therapeutic target for restoring diurnal metabolic BAT activity, and that efficiency of strategies targeting BAT may be improved by including time of day as an important factor. Show less
Morwani Mangnani, J.; Giannos, P.; Belzer, C.; Beekman, M.; Slagboom, P.E.; Prokopidis, K. 2022
Major hallmarks of functional loss, loss of metabolic and musculoskeletal health and (multi)morbidity with aging are associated with sleep disturbances. With poor sleep shifts in gut microbial... Show moreMajor hallmarks of functional loss, loss of metabolic and musculoskeletal health and (multi)morbidity with aging are associated with sleep disturbances. With poor sleep shifts in gut microbial composition commonly manifest, which could mediate the pro-inflammatory state between sleep disturbances and sarcopenia. This systematic review presents the recent evidence on how sleep disturbances throughout the lifespan associate with and contribute to gut microbial composition changes, proposing a mechanism to understand the etiology of sarcopenia through sleep disturbances. The relationship between disturbed sleep and clinically relevant gut microbiota composition on health aspects of aging is discussed. A search was performed in PubMed, Cochrane Library, Scopus, Web of Science using keywords including (microbio* OR microflora) AND (sleep OR sleep disorder). Six cross-sectional population-based studies and five experimental clinical trials investigating healthy individuals with ages ranging from 4 to 71 were included. The cross-sectional studies reported similarities in associations with sleep disturbance and gut microbial diversity. In older adults, shorter sleep duration is associated with an increase in pro-inflammatory bacteria whereas increasing sleep quality is positively associated with an increase of beneficial Verrucomicrobia and Lentisphaerae phyla. In young adults, the effect of sleep disruption on gut microbiome composition, specifically the ratio of beneficial Firmicutes over Bacteroidetes phyla, remains contradictory and unclear. The findings of this review warrant further research in the modulation of the gut microbiome linking poor sleep with muscle-catabolic consequences throughout the lifespan. Show less
Wiersema, J.M.; Kamphuis, A.E.P.; Rohling, J.H.T.; Kervezee, L.; Akintola, A.A.; Jansen, S.W.; ... ; Spoel, E. van der 2022
Aging is associated with changes in heart rate (HR), heart rate variability (HRV), and 24-h rhythms in HR. Longevity has been linked to lower resting HR, while a higher resting HR and a decreased... Show moreAging is associated with changes in heart rate (HR), heart rate variability (HRV), and 24-h rhythms in HR. Longevity has been linked to lower resting HR, while a higher resting HR and a decreased HRV were linked to cardiovascular events and increased mortality risk. HR and HRV are often investigated during a short electrocardiogram (ECG) measurement at a hospital. In this study, we aim to investigate the relationship between HR parameters with familial longevity and chronological age derived from continuous ambulatory ECG measurements collected over a period of 24 to 90 hours. We included 73 middle-aged participants (mean (SD) age: 67.0 (6.16) years), comprising 37 offspring of long-lived families, 36 of their partners, and 35 young participants (22.8 (3.96) years). We found no association with familial longevity, but middle-aged participants had lower 24-h HR (average and maximum HR, not minimum HR), lower amplitudes, and earlier trough and peak times than young participants. Associations in HR with chronological age could be caused by the aging process or by differences in environmental factors. Interestingly, middle-aged participants had a less optimal HRV during long-term recordings in both the sleep and awake periods, which might indicate that their heart is less adaptable than that of young participants. This could be a first indication of deteriorated cardiovascular health in middle-aged individuals. Show less
BACKGROUND: Cardioinhibition may diminish with age, but the changing balance of cardioinhibition and vasodepression with age has not been quantified, leaving the mechanism of vasovagal syncope (VVS... Show moreBACKGROUND: Cardioinhibition may diminish with age, but the changing balance of cardioinhibition and vasodepression with age has not been quantified, leaving the mechanism of vasovagal syncope (VVS) in old age unclear .OBJECTIVES: This study sought to quantify age-related changes of vasodepression and cardioinhibition in tilt-induced VVS. METHODS: We studied 163 cases of tilt-induced WS, evoked using the Italian protocol with blood pressure, heart rate, and video-etectroencephalographic monitoring. Presyncope was excluded. Cardioinhibition was defined as the heart rate decrease before syncope; asystotic pauses (>= 3 seconds) were divided into early and late asystole, ie, beginning early enough to or too late to be the major cause of toss of consciousness. The log-ratio method was used to quantify contributions of cardioinhibition and vasodepression, assessed in 2 10-second periods before the onset of cardioinhibition and before syncope. RESULTS: With increasing age, cardioinhibition decreased, ie, heart rate decreased less and more slowly near syncope (P < 0.0001), white vasodepression increased. Asystotic pauses were less frequent in the older one-half of the group than the younger one-half (26% vs 57%; P < 0.00001), but when it did, late asystole occurred more often (58% vs 15%; P < 0.001). CONCLUSIONS: The shift toward less cardioinhibition and more vasodepression with increased age probably reflects a physiological shift in circulatory control. The weakening of cardioinhibition with age may detract from the efficacy of pacing in older patients with VVS. Cardioinhibition-vasodepression balance should be considered in pacing decisions in older subjects with VVS. (C) 2022 by the American College of Cardiology Foundation. Show less
Houwen-van Opstal, S.L.S.; Heutinck, L.; Jansen, M.; Krom, Y.D.; Cup, E.H.C.; Hendriksen, J.G.M.; ... ; Groot, I.J.M. de 2021
Introduction/Aims: As life expectancy improves for patients with Duchenne muscular dystrophy (DMD), new symptoms are likely to arise. This aims of this study are: (1) to explore the prevalence of a... Show moreIntroduction/Aims: As life expectancy improves for patients with Duchenne muscular dystrophy (DMD), new symptoms are likely to arise. This aims of this study are: (1) to explore the prevalence of a broad variety of symptoms in the various stages of DMD (with and without steroid use); (2) to explore the prevalence of common secondary diagnoses; and (3) to evaluate the social participation level of patients with DMD older than 16 y of age; and to explore correlations between social participation and symptoms.Methods A cross-sectional self-report questionnaire, including questions on functional level and health status, as well as a standardized participation scale was distributed among Dutch patients with DMD.Results Eighty-four male patients with a mean age of 22.0 (SD = 10.0) y were enrolled. The most prevalent and limiting symptoms were difficulty coughing (58%), coldness of hands (57%), contractures (51%), stiffness (49%), fatigue (40%), myalgia (38%), and low speech volume (33%). Prevalent secondary diagnoses included cardiac disease (14%), neurobehavioral diagnosis (13%), low blood pressure (13%), and arthrosis (5%). Social participation correlated negatively with coldness of hands (r = - .29; P < .03), decreased intelligibility (r = - .40; P < .003), and chewing problems (r = - .33; P < .02).Discussion The prevalence of a broad spectrum of symptoms and secondary diagnoses is high in patients with DMD, and some of these symptoms are correlated with social participation. Growing awareness of new symptoms and secondary diagnoses among patients, caregivers, and professionals can enhance their recognition, possibly facilitating prevention and early treatment. Show less
Hassouneh, F.; Goldeck, D.; Pera, A.; Heemst, D. van; Slagboom, P.E.; Pawelec, G.; Solana, R. 2021
Cytomegalovirus (CMV) latent infection and aging contribute to alterations in the function and phenotype of the T-cell pool. We have demonstrated that CMV-seropositivity is associated with the... Show moreCytomegalovirus (CMV) latent infection and aging contribute to alterations in the function and phenotype of the T-cell pool. We have demonstrated that CMV-seropositivity is associated with the expansion of polyfunctional CD57+ T-cells in young and middle-aged individuals in response to different stimuli. Here, we expand our results on the effects of age and CMV infection on T-cell functionality in a cohort of healthy middle-aged and older individuals stratified by CMV serostatus. Specifically, we studied the polyfunctional responses (degranulation, IFN-gamma and TNF-alpha production) of CD4+, CD8+, CD8+CD56+ (NKT-like), and CD4-CD8- (DN) T-cells according to CD57 expression in response to Staphylococcal Enterotoxin B (SEB). Our results show that CD57 expression by T-cells is not only a hallmark of CMV infection in young individuals but also at older ages. CD57+ T-cells are more polyfunctional than CD57- T-cells regardless of age. CMV-seronegative individuals have no or a very low percentages of cytotoxic CD4+ T-cells (CD1017a+) and CD4+CD57+ T-cells, supporting the notion that the expansion of these T-cells only occurs in the context of CMV infection. There was a functional shift in T-cells associated with CMV seropositivity, except in the NKT-like subset. Here, we show that the effect of CMV infection and age differ among T-cell subsets and that CMV is the major driving force for the expansion of highly polyfunctional CD57+ T-cells, emphasizing the necessity of considering CMV serology in any study of immunosenescence. Show less
Heijningen, V.G. van; Cardol, M.; Heijningen-Tousain, H.J.M. van; Oosterveer, D.M.; Markus-Doornbosch, F. van; Sattoe, J.N.T.; ... ; Hilberink, S.R. 2021
Background: Adults with cerebral palsy (CP) may experience an increasing impact of their disability on daily life and this may interfere with their citizenship. Citizenship is a layered construct.... Show moreBackground: Adults with cerebral palsy (CP) may experience an increasing impact of their disability on daily life and this may interfere with their citizenship. Citizenship is a layered construct. Next to formal and theoretical significations, and civil rights acts such as the UN Convention on the Rights for Persons with Disabilities (CRPD), the meaning of citizenship is formed by the person themselves. The present study aimed to gain insight into what citizenship means for adults with CP 40 years or older and what is needed to support and pursue their citizenship to improve person-centered rehabilitation which can facilitate this process.Methods: Adults with CP (>40 years) without intellectual disability were recruited from medical records of a large rehabilitation center to participate in a qualitative study using the photovoice method. Participants were asked to take photos of objects or life situations that constituted citizenship for them; these photos were then the prompts for the semi-structured interviews that were held face-to-face at their homes. Background and clinical characteristics were gathered using a short face-to-face questionnaire. Data were analyzed through inductive thematic analysis.Results: Nineteen adults participated [mean age (SD) 57.8 (9.4) years (range 44-79), six men]. From the analysis four themes emerged: (a) Meanings of citizenship; (b) Citizenship: Facilitator and barriers; (c) Paradoxes of support and participation; and (d) Future. Furthermore, next to the ability to participate in society without restrictions, sense of belonging was reported to be an important aspect of "meanings of citizenship." The physiotherapist was perceived as an important health professional to maintain physical activity and deal with the impact of aging with CP on daily activities. Complex healthcare and support services regulations and aging affected citizenship negatively.Conclusion: Middle-aged and older adults with CP view citizenship as the ability to participate and belong in society. To optimize their citizenship the challenges and individual needs must be seen and supported by person-centered rehabilitation and support services. Simplification of complex healthcare and services regulations can further improve citizenship. Show less
Optimizing emergency care for the aging population is an important future challenge, as the proportion of older patients at the emergency department (ED) rapidly increases. Older patients,... Show moreOptimizing emergency care for the aging population is an important future challenge, as the proportion of older patients at the emergency department (ED) rapidly increases. Older patients, particularly those who are frail, have a high risk of adverse outcomes after an ED visit, such as functional decline, institutionalization, and death. The ED can have a key position in identifying frail older patients who benefit most from comprehensive geriatric care [including delirium preventive measures, early evaluation of after-discharge care, and a comprehensive geriatric assessment (CGA)]. However, performing extensive frailty assessment is not suitable at the ED. Therefore, quick and easy-to-use instruments are needed to identify older patients at risk for adverse outcomes. This narrative review outlines the importance and complexity of frailty assessment at the ED. It aligns the available screening instruments, including clinical judgment as frailty assessment, and summarizes arguments for and against frailty assessment at the ED. Show less
D'Aquila, P.; Giacconi, R.; Malavolta, M.; Piacenza, F.; Burkle, A.; Villanueva, M.M.; ... ; Bellizzi, D. 2021
The presence of circulating microbiome in blood has been reported in both physiological and pathological conditions, although its origins, identities and function remain to be elucidated. This... Show moreThe presence of circulating microbiome in blood has been reported in both physiological and pathological conditions, although its origins, identities and function remain to be elucidated. This study aimed to investigate the presence of blood microbiome by quantitative real-time PCRs targeting the 16S rRNA gene. To our knowledge, this is the first study in which the circulating microbiome has been analyzed in such a large sample of individuals since the study was carried out on 1285 Randomly recruited Age-Stratified Individuals from the General population (RASIG). The samples came from several different European countries recruited within the EU Project MARK-AGE in which a series of clinical biochemical parameters were determined. The results obtained reveal an association between microbial DNA copy number and geographic origin. By contrast, no gender and age-related difference emerged, thus demonstrating the role of the environment in influencing the above levels independent of age and gender at least until the age of 75. In addition, a significant positive association was found with Free Fatty Acids (FFA) levels, leukocyte count, insulin, and glucose levels. Since these factors play an essential role in both health and disease conditions, their association with the extent of the blood microbiome leads us to consider the blood microbiome as a potential biomarker of human health. Show less
Delineating the association of age and cortical thickness in healthy individuals is critical given the association of cortical thickness with cognition and behavior. Previous research has shown... Show moreDelineating the association of age and cortical thickness in healthy individuals is critical given the association of cortical thickness with cognition and behavior. Previous research has shown that robust estimates of the association between age and brain morphometry require large-scale studies. In response, we used cross-sectional data from 17,075 individuals aged 3-90 years from the Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) Consortium to infer age-related changes in cortical thickness. We used fractional polynomial (FP) regression to quantify the association between age and cortical thickness, and we computed normalized growth centiles using the parametric Lambda, Mu, and Sigma method. Interindividual variability was estimated using meta-analysis and one-way analysis of variance. For most regions, their highest cortical thickness value was observed in childhood. Age and cortical thickness showed a negative association; the slope was steeper up to the third decade of life and more gradual thereafter; notable exceptions to this general pattern were entorhinal, temporopolar, and anterior cingulate cortices. Interindividual variability was largest in temporal and frontal regions across the lifespan. Age and its FP combinations explained up to 59% variance in cortical thickness. These results may form the basis of further investigation on normative deviation in cortical thickness and its significance for behavioral and cognitive outcomes. Show less
One of the essential functions of microglia is to continuously sense changes in their environment and adapt to those changes. For this purpose, they use a set of genes termed the sensome. This... Show moreOne of the essential functions of microglia is to continuously sense changes in their environment and adapt to those changes. For this purpose, they use a set of genes termed the sensome. This sensome is comprised of the most abundantly expressed receptors on the surface of microglia. In this study, we updated previously identified mouse microglial sensome by incorporating an additional published RNAseq dataset into the data-analysis pipeline. We also identified members of the human microglial sensome using two independent human microglia RNAseq data sources. Using both the mouse and human microglia sensomes, we identified a key set of genes conserved between the mouse and human microglial sensomes as well as some differences between the species. We found a key set of 57 genes to be conserved in both mouse and human microglial sensomes. We define these genes as the "microglia core sensome". We then analyzed expression of genes in this core sensome in five different datasets from two neurodegenerative disease models at various stages of the diseases and found that, overall, changes in the level of expression of microglial sensome genes are specific to the disease or condition studied. Our results highlight the relevance of data generated in mice for understanding the biology of human microglia, but also stress the importance of species-specific gene sets for the investigation of diseases involving microglia. Defining this microglial specific core sensome may help identify pathological changes in microglia in humans and mouse models of human disease. Show less
Healthy individuals perform a task such as hitting the head of a nail with an infinite coordination spectrum. This motor redundancy is healthy and allows for learning through exploration and... Show moreHealthy individuals perform a task such as hitting the head of a nail with an infinite coordination spectrum. This motor redundancy is healthy and allows for learning through exploration and uniform load distribution across muscles. Assessing movement complexity within repetitive movement trajectories may provide insight into the available motor redundancy during aging. We quantified complexity of repetitive arm elevation trajectories in the aging shoulder and assessed test-retest reliability of this quantification. In a cross-sectional study using 3D-electromagnetic tracking, 120 asymptomatic subjects, aged between 18 and 70 years performed repetitive abduction and forward/anteflexion movements. Movement complexity was calculated using the Approximate Entropy (ApEn-value): [0,2], where lower values indicate reduced complexity. Thirty-three participants performed the protocol twice, to determine reliability (intraclass correlation coefficient [ICC]). The association between age and ApEn was corrected for task characteristics (e.g., sample length) with multiple linear regression analysis. Reproducibility was determined using scatter plots and ICC's. Higher age was associated with lower ApEn-values during abduction (unstandardized estimate: -0.003/year; 95% confidence interval: [-0.005; -0.002]; p < .001). ICC's revealed poor to good reliability depending on differences in sample length between repeated measurements. The results may imply more stereotype movement during abduction in the ageing shoulder, making this movement prone to the development of shoulder complaints. Future studies may investigate the pathophysiology and clinical course of shoulder complaints by assessment of movement complexity. To this end, the ApEn-value calculated over repetitive movement trajectories may be used, although biasing factors such as sample length should be taken into account. Show less
Cardelli, M.; Doorn, R. van; Larcher, L.; Donato, M. di; Piacenza, F.; Pierpaoli, E.; ... ; Kumar, R. 2020
Aim: To evaluate CpG methylation of long interspersed nuclear elements 1 (LINE-1) and human endogenous retrovirus K (HERV-K) retroelements as potential prognostic biomarkers in cutaneous melanoma.... Show moreAim: To evaluate CpG methylation of long interspersed nuclear elements 1 (LINE-1) and human endogenous retrovirus K (HERV-K) retroelements as potential prognostic biomarkers in cutaneous melanoma. Materials & methods: Methylation of HERV-K and LINE-1 retroelements was assessed in resected melanoma tissues from 82 patients ranging in age from 14 to 88 years. In addition, nevi from eight patients were included for comparison with nonmalignant melanocytic lesions. Results: Methylation levels were lower in melanomas than in nevi. HERV-K and LINE-1 methylation were decreased in melanoma patients with clinical parameters associated with adverse prognosis, while they were independent of age and gender. Hypomethylation of HERV-K (but not LINE-1) was an independent predictor of reduced disease-free survival. Conclusion: HERV-K hypomethylation can be a potential independent biomarker of melanoma recurrence. Show less
Endo, Y.; Baldino, K.; Li, B.; Zhang, Y.T.; Sakthivel, D.; MacArthur, M.; ... ; Sinha, I. 2020
The ability of skeletal muscle to regenerate declines significantly with aging. The expression of aryl hydrocarbon receptor nuclear translocator (ARNT), a critical component of the hypoxia... Show moreThe ability of skeletal muscle to regenerate declines significantly with aging. The expression of aryl hydrocarbon receptor nuclear translocator (ARNT), a critical component of the hypoxia signaling pathway, was less abundant in skeletal muscle of old (23-25 months old) mice. This loss of ARNT was associated with decreased levels of Notch1 intracellular domain (N1ICD) and impaired regenerative response to injury in comparison to young (2-3 months old) mice. Knockdown of ARNT in a primary muscle cell line impaired differentiation in vitro. Skeletal muscle-specific ARNT deletion in young mice resulted in decreased levels of whole muscle N1ICD and limited muscle regeneration. Administration of a systemic hypoxia pathway activator (ML228), which simulates the actions of ARNT, rescued skeletal muscle regeneration in both old and ARNT-deleted mice. These results suggest that the loss of ARNT in skeletal muscle is partially responsible for diminished myogenic potential in aging and activation of hypoxia signaling holds promise for rescuing regenerative activity in old muscle. Show less
Akker, E.B. van den; Trompet, S.; Wolf, J.J.H.B.; Beekman, M.; Suchiman, H.E.D.; Deelen, J.; ... ; Slagboom, P.E. 2020
BACKGROUND: The blood metabolome incorporates cues from the environment and the host's genetic background, potentially offering a holistic view of an individual's health status.METHODS: We have... Show moreBACKGROUND: The blood metabolome incorporates cues from the environment and the host's genetic background, potentially offering a holistic view of an individual's health status.METHODS: We have compiled a vast resource of proton nuclear magnetic resonance metabolomics and phenotypic data encompassing over 25 000 samples derived from 26 community and hospital-based cohorts.RESULTS: Using this resource, we constructed a metabolomics-based age predictor (metaboAge) to calculate an individual's biological age. Exploration in independent cohorts demonstrates that being judged older by one's metabolome, as compared with one's chronological age, confers an increased risk on future cardiovascular disease, mortality, and functionality in older individuals. A web-based tool for calculating metaboAge (metaboage.researchlumc.nl) allows easy incorporation in other epidemiological studies. Access to data can be requested at bmri.nl/samples-images-data.CONCLUSIONS: In summary, we present a vast resource of metabolomics data and illustrate its merit by constructing a metabolomics-based score for biological age that captures aspects of current and future cardiometabolic health. Show less
Biomarkers of aging are urgently needed to identify individuals at high risk of developing age-associated disease or disability. Growing evidence from population-based studies points to whole-body... Show moreBiomarkers of aging are urgently needed to identify individuals at high risk of developing age-associated disease or disability. Growing evidence from population-based studies points to whole-body magnetic resonance imaging's (MRI) enormous potential for quantifying subclinical disease burden and for assessing changes that occur with aging in all organ systems. The Aging Imageomics Study aims to identify biomarkers of human aging by analyzing imaging, biopsychosocial, cardiovascular, metabolomic, lipidomic, and microbiome variables. This study recruited 1030 participants aged >= 50 years (mean 67, range 50-96 years) that underwent structural and functional MRI to evaluate the brain, large blood vessels, heart, abdominal organs, fat, spine, musculoskeletal system and ultrasonography to assess carotid intima-media thickness and plaques. Patients were notified of incidental findings detected by a certified radiologist when necessary. Extensive data were also collected on anthropometrics, demographics, health history, neuropsychology, employment, income, family status, exposure to air pollution and cardiovascular status. In addition, several types of samples were gathered to allow for microbiome, metabolomic and lipidomic profiling. Using big data techniques to analyze all the data points from biological phenotyping together with health records and lifestyle measures, we aim to cultivate a deeper understanding about various biological factors (and combinations thereof) that underlie healthy and unhealthy aging. Show less
Berg, N. van den; Rodriguez-Girondo, M.; Mandemakers, K.; Janssens, A.A.P.O.; Beekman, M.; Slagboom, P.E. 2020
Loci associated with longevity are likely to harbor genes coding for key players of molecular pathways involved in a lifelong decreased mortality and decreased/compressed morbidity. However,... Show moreLoci associated with longevity are likely to harbor genes coding for key players of molecular pathways involved in a lifelong decreased mortality and decreased/compressed morbidity. However, identifying such loci is challenging. One of the most plausible reasons is the uncertainty in defining long-lived cases with the heritable longevity trait among long-living phenocopies. To avoid phenocopies, family selection scores have been constructed, but these have not yet been adopted as state of the art in longevity research. Here, we aim to identify individuals with the heritable longevity trait by using current insights and a novel family score based on these insights. We use a unique dataset connecting living study participants to their deceased ancestors covering 37,825 persons from 1,326 five-generational families, living between 1788 and 2019. Our main finding suggests that longevity is transmitted for at least two subsequent generations only when at least 20% of all relatives are long-lived. This proves the importance of family data to avoid phenocopies in genetic studies. Show less
Background: Aging is associated with diminished testosterone (Te) secretion, which may be attributed to Leydig cell dysfunction, decreased pituitary stimulation, and altered Te feedback.Objective:... Show moreBackground: Aging is associated with diminished testosterone (Te) secretion, which may be attributed to Leydig cell dysfunction, decreased pituitary stimulation, and altered Te feedback.Objective: To study all regulatory nodes-gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH) and Leydig cell-in the same cohort of healthy men.Study Design: This was a placebo-controlled, blinded, prospectively randomized cross-over study in 40 men, age range 19 to 73 years, and body mass index (BMI) range 20 to 34.3 kg/m(2). A submaximal dose of the GnRH antagonist ganirelix was used to assess outflow of GnRH, by calculating the difference between LH output during the control arm and ganirelix arm. Ketoconazole (a steroidogenic inhibitor) was used to estimate feedback, by the difference in LH output during the ketoconazole and control arm. High-dose ganirelix and repeated LH infusions were used to measure testicular responsivity. Blood sampling was performed at 10-minute intervals.Results: There were age-related, but not body composition-related decreases in estimated GnRH secretion, the feedback strength of Te on LH, and Leydig cell responsivity to LH, accompanied by changes in approximate entropy. Bioavailable Te levels were negatively related to both age and computed tomography (CT)-estimated abdominal visceral mass (AVF), without interaction between these variables. The LH response to a submaximal dose of GnRH was independent of age and AVF.Conclusion: Advancing age is associated with (1) attenuated bioavailable Te secretion caused by diminished GnRH outflow and not by decreased GnRH responsivity of the gonadotrope, (2) diminished testicular responsivity to infused LH pulses, and (3) partial compensation by diminished Te feedback on central gonadotropic regulation. Show less
Blood pressure (BP) is a leading global risk factor. Increasing age is related to changes in cardiovascular physiology that could influence cuff BP measurement, but this has never been examined... Show moreBlood pressure (BP) is a leading global risk factor. Increasing age is related to changes in cardiovascular physiology that could influence cuff BP measurement, but this has never been examined systematically and was the aim of this study. Cuff BP was compared with invasive aortic BP across decades of age (from 40 to 89 years) using individual-level data from 31 studies (1674 patients undergoing coronary angiography) and 22 different cuff BP devices (19 oscillometric, 1 automated auscultation, 2 mercury sphygmomanometry) from the Invasive Blood Pressure Consortium. Subjects were aged 64 +/- 11 years, and 32% female. Cuff systolic BP overestimated invasive aortic systolic BP in those aged 40 to 49 years, but with each older decade of age, there was a progressive shift toward increasing underestimation of aortic systolic BP (P<0.0001). Conversely, cuff diastolic BP overestimated invasive aortic diastolic BP, and this progressively increased with increasing age (P<0.0001). Thus, there was a progressive increase in cuff pulse pressure underestimation of invasive aortic PP with increasing decades of age (P<0.0001). These age-related trends were observed across all categories of BP control. We conclude that cuff BP as an estimate of aortic BP was substantially influenced by increasing age, thus potentially exposing older people to greater chance for misdiagnosis of the true risk related to BP. Show less
Dim-light-at-night (DLAN) exposure is associated with health problems, such as metabolic disruptions, immunological modulations, oxidative stress, sleep problems, and altered circadian timing.... Show moreDim-light-at-night (DLAN) exposure is associated with health problems, such as metabolic disruptions, immunological modulations, oxidative stress, sleep problems, and altered circadian timing. Neurophysiological parameters, including sleep patterns, are altered in the course of aging in a similar way. Here, we investigated the effect of chronic (three months) DLAN exposure (12 L:12 Dim-light, 75:5 lux) on sleep and the sleep electroencephalogram (EEG), and rest-activity behavior in young (6-month-old, n = 9) and aged (18- n = 8, 24-month-old, n = 6) C57BL/6J mice and compared with age-matched controls (n = 11, n = 9 and n = 8, respectively). We recorded the EEG and electromyogram continuously for 48-h and conducted a 6-h sleep-deprivation. A delay in the phase angle of entrainment of locomotor activity and daily vigilance state rhythms was apparent in mice following DLAN exposure, throughout the whole age spectrum, rendering sleep characteristics similar among the three age DLAN groups and significantly different from the age-matched controls. Notably, slow-wave-activity in NREM sleep (SWA, EEG power density in 0.5-4.0 Hz) was differentially altered in young and aged DLAN mice. Particularly, SWA increased as a function of age, which was further accentuated following DLAN exposure. However, this was not found in the young DLAN animals, which were characterized by the lowest SWA levels. Concluding, long-term DLAN exposure induced more pronounced alterations in the sleep architecture of young mice, towards an aging phenotype, while it enhanced age-associated sleep changes in the older groups. Our data suggest that irrespective of age, chronic DLAN exposure deteriorates sleep behavior and may consequently impact general health. (C) 2019 IBRO. Published by Elsevier Ltd. All rights reserved. Show less
