SciCombinator

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Journal: Age (Dordrecht, Netherlands)

179

The reproductive-cell cycle theory of aging posits that reproductive hormone changes associated with menopause and andropause drive senescence via altered cell cycle signaling. Using data from the Wisconsin Longitudinal Study (n = 5,034), we analyzed the relationship between longevity and menopause, including other factors that impact “ovarian lifespan” such as births, oophorectomy, and hormone replacement therapy. We found that later onset of menopause was associated with lower mortality, with and without adjusting for additional factors (years of education, smoking status, body mass index, and marital status). Each year of delayed menopause resulted in a 2.9% reduction in mortality; after including a number of additional controls, the effect was attenuated modestly but remained statistically significant (2.6% reduction in mortality). We also found that no other reproductive parameters assessed added to the prediction of longevity, suggesting that reproductive factors shown to affect longevity elsewhere may be mediated by age of menopause. Thus, surgical and natural menopause at age 40, for example, resulted in identical survival probabilities. These results support the maintenance of the hypothalamic-pituitary-gonadal axis in homeostasis in prolonging human longevity, which provides a coherent framework for understanding the relationship between reproduction and longevity.

Concepts: Oophorectomy, Life expectancy, Gerontology, Organism, Hormone, Senescence, Ageing, Menopause

177

Consistent daily rhythms are important to healthy aging according to studies linking disrupted circadian rhythms with negative health impacts. We studied the effects of age and exercise on baseline circadian rhythms and on the circadian system’s ability to respond to the perturbation induced by an 8 h advance of the light:dark (LD) cycle as a test of the system’s robustness. Mice (male, mPer2(luc)/C57BL/6) were studied at one of two ages: 3.5 months (n = 39) and >18 months (n = 72). We examined activity records of these mice under entrained and shifted conditions as well as mPER2::LUC measures ex vivo to assess circadian function in the suprachiasmatic nuclei (SCN) and important target organs. Age was associated with reduced running wheel use, fragmentation of activity, and slowed resetting in both behavioral and molecular measures. Furthermore, we observed that for aged mice, the presence of a running wheel altered the amplitude of the spontaneous firing rate rhythm in the SCN in vitro. Following a shift of the LD cycle, both young and aged mice showed a change in rhythmicity properties of the mPER2::LUC oscillation of the SCN in vitro, and aged mice exhibited longer lasting internal desynchrony. Access to a running wheel alleviated some age-related changes in the circadian system. In an additional experiment, we replicated the effect of the running wheel, comparing behavioral and in vitro results from aged mice housed with or without a running wheel (>21 months, n = 8 per group, all examined 4 days after the shift). The impact of voluntary exercise on circadian rhythm properties in an aged animal is a novel finding and has implications for the health of older people living with environmentally induced circadian disruption.

Concepts: Chronobiology, Gerontology, Ageing, Circadian rhythms, Circadian rhythm

175

Type 2 diabetes is known to cause endothelial activation resulting in the secretion of von Willebrand factor (VWF). We have shown that levels of VWF in a glycoprotein Ib-binding conformation are increased in specific clinical settings. The aim of the current study is to investigate whether active VWF levels increase during aging and the development of diabetes within the population of patients suffering from type 2 diabetes. Patients and controls were divided into two groups based on age: older and younger than 60 years of age. VWF antigen, VWF propeptide, VWF activation factor and total active VWF were measured. Patients older than 60 years of age had increased levels of total active VWF, VWF activation factor and VWF propeptide compared to younger patients and controls. All measured VWF parameters were associated with age in diabetic patients. Total active VWF and VWF propeptide correlated with the period of being diagnosed with diabetes. Regression analyses showed that especially the VWF activation factor was strongly associated with diabetes in patients older than 60 years of age. In conclusion, we found that the conformation of VWF could be involved in the disease process of diabetes and that the VWF in a glycoprotein Ib-binding conformation could play a role as risk marker during the development of diabetes in combination with an increase in age. Our study shows that the active quality of VWF was more important than the quantity.

Concepts: Heyde's syndrome, Diabetes mellitus, Weibel-Palade body, Insulin, Diabetes mellitus type 2, Platelet, Von Willebrand disease, Von Willebrand factor

164

Aging is a complex physiological process that poses considerable conundrums to rapidly aging societies. For example, the risk of dying from cardiovascular diseases and/or cancer steadily declines for people after their 60s, and other causes of death predominate for seniors older than 80 years of age. Thus, physiological aging presents numerous unanswered questions, particularly with regard to changing metabolic patterns. Urine proteomics analysis is becoming a non-invasive and reproducible diagnostic method. We investigated the urine proteomes in healthy elderly people to determine which metabolic processes were weakened or strengthened in aging humans. Urine samples from 37 healthy volunteers aged 19-90 years (19 men, 18 women) were analyzed for protein expression by liquid chromatography-tandem mass spectrometry. This generated a list of 19 proteins that were differentially expressed in different age groups (young, intermediate, and old age). In particular, the oldest group showed protein changes reflective of altered extracellular matrix turnover and declining immune function, in which changes corresponded to reported changes in cardiovascular tissue remodeling and immune disorders in the elderly. Thus, urinary proteome changes in the elderly appear to reflect the physiological processes of aging and are particularly clearly represented in the circulatory and immune systems. Detailed identification of “protein trails” creates a more global picture of metabolic changes that occur in the elderly.

Concepts: Aging, Retirement, Immune system, Blood, Old age, Ageing, Death, Gerontology

29

Estimating perceived age by facial photographs is a good estimate of health in elderly populations. Previously, we showed that familial longevity is marked by a more beneficial glucose metabolism already at middle age. As glucose is also related to skin aging, this study aimed to investigate the association between glucose metabolism and perceived age. Perceived age was assessed using facial photographs and non-fasted glucose and insulin were measured in 602 subjects from the Leiden Longevity Study. Non-diabetic subjects (n = 569) were divided in three strata according to their glucose levels, and diabetic subjects (n = 33; as a proxy of long-term hyperglycemic exposure) were included as a fourth stratum. Considered confounding factors were gender, chronological age, current smoking, body mass index, photo-damage score, and insulin levels. Perceived age was increased from 59.6 years (SE = 0.3) in the first stratum to 61.2 years (SE = 0.6) in diabetic subjects (p for trend = 0.002). In non-diabetic subjects only, perceived age was increased from 59.6 years (SE = 0.3) in the first stratum to 60.6 years (SE = 0.3) in the third stratum (p for trend = 0.009). Continuously, perceived age increased 0.40 years (SE = 0.14, p = 0.006) per 1 mmol/L increase in glucose level in non-diabetic subjects. The present study demonstrates that, also among non-diabetic subjects, higher glucose levels are associated with a higher perceived age. Future research should be focused on elucidating possible mechanisms linking glucose levels to perceived age.

Concepts: Body mass index, Obesity, Gerontology, Carbohydrate, Nutrition, Diabetes mellitus, Insulin, Blood sugar

27

Aging is associated with decline in cardiovascular, autonomic function, and brain-derived neurotropic factor (BDNF). Reports are scanty regarding whether yoga can improve age-related degenerative changes in healthy active men. This study is designed to appraise the role of yoga in improving age-related degenerative changes in cardiometabolic risk profile, autonomic function, stress, and BDNF. Healthy active males of three age groups (20-29, 30-39, and 40-49 years) were randomly assigned to practice yoga daily 1 h for 3 months. Significantly higher values of heart rate (HR), blood pressure (BP), load in heart (DoP), myocardial oxygen consumption (RPP), and total cholesterol (TC) were noted in senior age group. HR, BP, DoP, RPP, and TC decreased significantly following yogic practice. High frequency (HF), total power (TP), all time domain variables of heart rate variability (HRV), and skin conductance (SC) were significantly decreased with advancement of age. HF, TP, and time domain parameters of HRV and SC increased significantly following yogic practice. Higher levels of catecholamines and low frequency (LF) power of HRV was noted with advancement of age. Levels of catecholamines and LF significantly decreased following yogic practice. Cortisol and adrenocorticotropic hormone (ACTH) level raised in senior age group. BDNF, serotonin, and dopamine were low in higher age group. Significant decrement of cortisol; ACTH; and increment in serotonin, dopamine, and BDNF was noted following yogic practice. This study revealed that yogic practices might help in the prevention of age-related degeneration by changing cardiometabolic risk factors, autonomic function, and BDNF in healthy male.

Concepts: Addison's disease, Autonomic nervous system, Blood, Cortisol, Circulatory system, Adrenal cortex, Adrenocorticotropic hormone, Heart

23

Increased vascular stiffness, endothelial dysfunction, and isolated systolic hypertension are hallmarks of vascular aging. Regular cocoa flavanol (CF) intake can improve vascular function in healthy young and elderly at-risk individuals. However, the mechanisms underlying CF bioactivity remain largely unknown. We investigated the effects of CF intake on cardiovascular function in healthy young and elderly individuals without history, signs, or symptoms of cardiovascular disease by applying particular focus on functional endpoints relevant to cardiovascular aging. In a randomized, controlled, double-masked, parallel-group dietary intervention trial, 22 young (<35 years) and 20 elderly (50-80 year) healthy, male non-smokers consumed either a CF-containing drink (450 mg CF) or nutrient-matched, CF-free control drink bi-daily for 14 days. The primary endpoint was endothelial function as measured by flow-mediated vasodilation (FMD). Secondary endpoints included cardiac output, vascular stiffness, conductance of conduit and resistance arteries, and perfusion in the microcirculation. Following 2 weeks of CF intake, FMD improved in young (6.1 ± 0.7 vs. 7.6 ± 0.7 %, p < 0.001) and elderly (4.9 ± 0.6 vs. 6.3 ± 0.9 %, p < 0.001). Secondary outcomes demonstrated in both groups that CF intake decreased pulse wave velocity and lowered total peripheral resistance, and increased arteriolar and microvascular vasodilator capacity, red cell deformability, and diastolic blood pressure, while cardiac output remained affected. In the elderly, baseline systolic blood pressure was elevated, driven by an arterial-stiffness-related augmentation. CF intake decreased aortic augmentation index (-9 %) and thus systolic blood pressure (-7 mmHg; Clinicaltrials.gov: NCT01639781). CF intake reverses age-related burden of cardiovascular risk in healthy elderly, highlighting the potential of dietary flavanols to maintain cardiovascular health.

Concepts: Cardiac cycle, Myocardial infarction, Artery, Cardiovascular system, Atherosclerosis, Blood, Hypertension, Blood pressure

20

Mitochondria produce cellular energy but also free-radicals, which damage cells despite an array of endogenous anti-oxidants. In Northern Europe, the mitochondrial haplogroup J has been related to longevity in nonagenarians and centenarians but also with age-related disease. Hypertension is an important contributor to atherosclerotic-related diseases and its pathogenesis is associated with increased oxidative stress. In this study, we questioned whether J haplogroup octo/nonagenarians from the Belfast Elderly Longitudinal Free-living Elderly STudy (BELFAST) study showed evidence of protective blood pressure or anti-oxidant profile which might explain their longevity advantage. Briefly, in a cross-sectional study, community-living, mentally alert (Folstein >25/30), octo/nonagenarian subjects, recruited for good health, were enlisted and consented as part of the BELFAST study, for blood pressure, anthropometric measurements and blood sampling. DNA typing for mitochondrial haplotypes was carried out with measurements for enzymatic and non-enzymatic antioxidants. J haplogroup carriers showed lower systolic blood pressure and glutathione peroxidase activity (Gpx) with higher folate measurements. There was no change in urate, bilirubin, albumin or nutrition-related antioxidants-selenium or vitamins A, C and α and β carotene. BELFAST study mtDNA J haplogroup octo/nonagenarians showed lower blood pressure and reduced glutathione peroxidase activity and higher folate, but no change for other antioxidants. These findings are of interest in view of mtDNA J haplogroup’s association with increased age in some previous studies.

Concepts: Metabolism, DNA, Oxidative phosphorylation, Oxidative stress, Reactive oxygen species, Glutathione, Glutathione peroxidase, Antioxidant

18

This randomized controlled trial examined the effects of multicomponent training on muscle power output, muscle mass, and muscle tissue attenuation; the risk of falls; and functional outcomes in frail nonagenarians. Twenty-four elderly (91.9 ± 4.1 years old) were randomized into intervention or control group. The intervention group performed a twice-weekly, 12-week multicomponent exercise program composed of muscle power training (8-10 repetitions, 40-60 % of the one-repetition maximum) combined with balance and gait retraining. Strength and power tests were performed on the upper and lower limbs. Gait velocity was assessed using the 5-m habitual gait and the time-up-and-go (TUG) tests with and without dual-task performance. Balance was assessed using the FICSIT-4 tests. The ability to rise from a chair test was assessed, and data on the incidence and risk of falls were assessed using questionnaires. Functional status was assessed before measurements with the Barthel Index. Midthigh lower extremity muscle mass and muscle fat infiltration were assessed using computed tomography. The intervention group showed significantly improved TUG with single and dual tasks, rise from a chair and balance performance (P < 0.01), and a reduced incidence of falls. In addition, the intervention group showed enhanced muscle power and strength (P < 0.01). Moreover, there were significant increases in the total and high-density muscle cross-sectional area in the intervention group. The control group significantly reduced strength and functional outcomes. Routine multicomponent exercise intervention should be prescribed to nonagenarians because overall physical outcomes are improved in this population.

Concepts: Randomized controlled trial, Thigh, Muscular system, Physical exercise, Muscle

13

The complex mixture of phytochemicals in fruits and vegetables provides protective health benefits, mainly through additive and/or synergistic effects. The presence of several bioactive compounds, such as polyphenols and caffeine, implicates coffee as a potential nutritional therapeutic in aging. Moderate (three to five cups a day) coffee consumption in humans is associated with a significant decrease in the risk of developing certain chronic diseases. However, the ability of coffee supplementation to improve cognitive function in aged individuals and the effect of the individual components in coffee, such as caffeine, have not been fully evaluated. We fed aged rats (19 months) one of five coffee-supplemented diets (0, 0.165, 0.275, 0.55, and 0.825 % of the diet) for 8 weeks prior to motor and cognitive behavior assessment. Aged rats supplemented with a 0.55 % coffee diet, equivalent to ten cups of coffee, performed better in psychomotor testing (rotarod) and in a working memory task (Morris water maze) compared to aged rats fed a control diet. A diet with 0.55 % coffee appeared to be optimal. The 0.165 % coffee-supplemented group (three cups) showed some improvement in reference memory performance in the Morris water maze. In a subsequent study, the effects of caffeine alone did not account for the performance improvements, showing that the neuroprotective benefits of coffee are not due to caffeine alone, but rather to other bioactive compounds in coffee. Therefore, coffee, in achievable amounts, may reduce both motor and cognitive deficits in aging.

Concepts: Death, Caffeine, Improve, Coffee, Cognitive psychology, Better, Cognition, Psychology