Age-associated cardiovascular changes in health: impact on cardiovascular disease in older persons

Gene expression profiling of aging in multiple mouse strains: identification of aging biomarkers and impact of dietary antioxidants

We used DNA microarrays to identify panels of transcriptional markers of aging that are differentially expressed in young (5 month) and old (25 month) mice of multiple inbred strains (129sv, BALB/c, CBA, DBA, B6, C3H and B6C3F(1)). In the heart, age-related changes of five genes were studied throughout the mouse lifespan: complement component 4, chemokine ligand 14, component of Sp100-rs, phenylalanine hydroxylase and src family associated phosphoprotein 2. A similar analysis in the brain (cerebellum) involved complement component 1q (alpha polypeptide), complement component 4, P lysozyme structural, glial fibrillary acidic protein and cathepsin S. Caloric restriction (CR) inhibited age-related expression of these genes in both tissues. Parametric analysis of gene set enrichment identified several biological processes that are induced with aging in multiple mouse strains. We also tested the ability of dietary antioxidants to oppose these transcriptional markers of aging. Lycopene, resveratrol, acetyl-l-carnitine and tempol were as effective as CR in the heart, and alpha-lipoic acid and coenzyme Q(10) were as effective as CR in the cerebellum. These findings suggest that transcriptional biomarkers of aging in mice can be used to estimate the efficacy of aging interventions on a tissue-specific basis.

Estrogen, aging and the cardiovascular system

Estrogen is a powerful hormone with pleiotropic effects. Estrogens have potent antioxidant effects and are able to reduce inflammation, induce vasorelaxation and alter gene expression in both the vasculature and the heart. Estrogen treatment of cultured cardiac myocytes and endothelial cells rapidly activates NFkappaB, induces heat-shock protein (HSP)-72, a potent intracellular protective protein, and protects cells from simulated ischemia. In in vivo models, estrogens protect against ischemia and trauma/hemorrhage. Estrogens may decrease the expression of soluble epoxide hydrolase, which has deleterious effects on the cardiovascular system through metabolism of epoxyeicosatrienoic acids. Natural (endogenous) estrogens in premenopausal women appear to protect against cardiovascular disease and yet controlled clinical trials have not indicated a benefit from estrogen replacement postmenopause. Much remains to be understood in regards to the many properties of this powerful hormone and how changes in this hormone interact with aging-associated changes. The unexpected negative results of trials of estrogen replacement postmenopause probably arise from our lack of understanding of the many effects of this hormone.

Association between arterial compliance and age in participants 9 to 77 years old

We characterized the age-related change in large and small artery compliance in 137 healthy participants between 9 and 77 years of age. Large artery compliance, measured by diastolic pulse contour analysis, had a sharp positive linear trend (0.89 mL x mm Hg( -1) x year(-1)) highly correlated with age in participants younger than 30 years (r = .76, p <.0001), had a slight negative trend (-0.10 mL x mm Hg(-1) x year(-1)) not significantly associated with age (r = -.11, p = .532) in middle-aged participants, and had a sharper negative trend (-0.19 mL x mm Hg(-1) x year(-1)) significantly associated with age (r = -.30, p =.023) in participants beyond 50 years. Similar results were found for small artery compliance. Large and small artery compliance increase in children, adolescents, and young adults, reach plateaus near age 30, and then decline beyond 30 years of age in those free of cardiovascular disease and risk factors.

Influence of age on blood pressure recovery after maximal effort ergometer exercise in non-athletic adult males

This study investigated whether age influences blood pressure recovery after maximal exercise in adult males. Forty healthy, non-athletic adult males (20 young, aged 22 +/- 3.46 years and 20 older, aged 48 +/- 6.91 years) participated in the study. Subjects performed a maximal-effort ergometer exercise test. Peak oxygen uptake (VO2max) was measured during the exercise protocol; heart rate (HR) and blood pressure (BP) were measured before exercise, during exercise (at 2-min intervals), and at the first minute of post-exercise recovery and subsequently at 2-min intervals until the recovery of BP. Results indicated that young adults had lower systolic blood pressure (SBP) recovery ratio (P < 0.05), lower SBP recovery time (P < 0.001), higher SBP% decline in 1, and 3 min (P < 0.001), and higher DBP% decline in 1, and 3 min (P < 0.05, <0.001) than the older adults, thus indicating faster BP recovery in young than older adults. A bivariate correlation test, revealed significant associations (P < 0.001, <0.01) between age and BP recovery parameters: percentage SBP decline in 1 and 3 min (27 and 39%), percentage DBP decline in 1 and 3 min (14 and 26%), third minute SBP ratio (22%), and SBP recovery time (72%). After controlling for factors affecting BP recovery such as resting SBP, percentage HR decline, VO2max and delta SBP, the observed correlations reduced in SBP recovery time (29%; P < 0.002) but disappeared (P > 0.01) in the other BP recovery parameters. These data indicate the need to take into account, factors affecting BP recovery when interpreting the effect of age on BP responses after exercise in future investigations.

Wireless blood velocity spectra measurement system for healthcare evaluation: reference data

The aim of the present study was to determine the blood velocity and its indices in common carotid artery (CCA) as reference value for clinical and healthcare application using the constructed portable wireless Doppler blood flow velocimeter system. Evaluation of CCA blood velocity waveforms was performed in 202 healthy volunteers in the age range of 20 to 69 years. Multivariate analysis was used to determine the relationship between the fixed factor and the outcome hemodynamic variables after adjustment for the related covariates. Results show a general age-related decrease in flow velocities and change in the velocity waveform. There is also a gender difference in velocity indices, except for peak systolic blood velocity. Gender difference is also found in systolic and pulse blood pressures. The findings suggest that waveform indices provide a more reliable evaluation of effects of aging and gender on CCA flow. In conclusion, normal CCA blood velocity parameters are determined in a total of 202 healthy volunteers between the third and seventh age decade after adjustment for gender and exercise effects. Findings may contribute to improved means of healthcare monitoring and clinical evaluation.

Influence of group training frequency on arterial stiffness in elderly women

We evaluated the effects of different training frequencies on arterial stiffness. 77 elderly women (mean 68.8 years and 7.0 SD) were divided into two training (1DW and 2DW) and a CONTROL group (n = 23). 1DW (n = 29) participated in 90-min group training once a week for 12 weeks, while 2DW (n = 25) attended twice a week. Each training program included recreational activities, six to eight resistance exercises for circuit training, and leg exercises for chair-based exercise. Brachial systolic and diastolic blood pressures and the brachial-to-ankle pulse-wave velocity (baPWV) were obtained in the supine position. Muscle strength and ventilatory threshold were also measured. After the training program, a reduction (P < 0.01) in baPWV was observed in 2DW (-7.8 +/- 7.0%) but not in 1DW (-1.5 +/- 7.5%) and CONTROL (-0.4 +/- 7.5%) without any changes in other measurements. The results suggest that, in order to improve arterial stiffness, an exercise frequency of at least twice a week is to be recommended for elderly.

A study of presbycardia, with gender differences favoring ageing women

BACKGROUND

The impact of ageing on the human cardiovascular system has been the subject of several studies in recent years, but with insufficient emphasis on defining sex-specific differences. To rectify this, gender-specific differences in structure and function in the human cardiovascular system were studied in a European population during natural ageing.

METHODS

Cardiac power output (CPO) was measured and integrated with changes in left ventricular (LV) mass, diastolic, systolic and limb blood flow, blood pressure and exercise capacity in 93 health-screened men and 122 women, aged 20 to 75 years.

RESULTS

Correlating with a 21% loss of LV mass, maximum cardiac pumping (i.e. CPOmax=QmaxxMAPmax) and reserve (CR=CPOmax-CPOrest) capacities decreased 20-25% with age in male hearts. In contrast, CPOmax, CR and LV mass were all preserved in ageing women. Maximum cardiac output (Qmax; 26-32%), peak forearm blood flow (FBFpeak; 61%) and exercise capacity (40-50%) all decreased, but more so in men than women. In contrast, systemic vascular resistance (68-75%) and mean arterial pressure (MAPmax; 14-26%) increased in both sexes. CPOrest decreased 27% in men, but was unchanged in women, despite lower early:late diastolic filling (48-51%), Qrest (19-23%) and FBFrest (56%) in both sexes.

CONCLUSIONS

Understanding sex-specific differences in cardiovascular ageing is important for public health and biomedical research, given increasingly larger older populations and the need to prevent and treat cardiovascular disease.

Association between lower-extremity function and arterial compliance in older adults

The purpose was to identify the association between lower-extremity function and arterial compliance in older men and women. Participants included 46 healthy men (n = 18) and women (n = 28) 60 years of age or older. Lower-extremity functional performance was assessed by the summary performance score (SPS) that includes tests of 5 timed repeated chair rises, standing balance, and 4-meter walking velocity. Arterial compliance and arterial pressure were analyzed through pulsewave analysis. Small arterial compliance (3.74 +/- 2.14; mean +/- SD) was related (r = 0.34, P = .028) to SPS (11.09 +/- 1.19) after adjusting for body surface area, hyperlipidemia, and hypertension. Systolic blood pressure (138 +/- 14) also was related to SPS (r = -0.314, P = .040). These results suggest diminished lower-extremity function is associated with decreased small arterial compliance and elevated arterial pressure in older men and women.

Analysis of the effect of ageing on rising edge characteristics of the photoplethysmogram using a modified Windkessel model

Ageing is one of the main contributing factors towards increasing arterial stiffness, leading to changes in peripheral pulses propagation. Therefore the characteristics of the photoplethysmogram (PPG) pulse, especially the rising edge and peak position, are greatly affected. In this study, the PPG pulse rising edge and corresponding peak position have been investigated non-invasively in human subjects as a function of age. Fifteen healthy subjects were selected and grouped in five age intervals, from 20 to 59 years, based on their comparable systolic-diastolic blood pressure and PPG amplitude. As expected, the peripheral pulse shows a steep rise and early peak in younger subjects. With age, the slope becomes blunted and in older subjects, the rise is very gradual and the pulse peak appears much later. Qualitative results were further verified by a modified 10-element Windkessel model to quantify the lumped parameter changes with ageing. This verification highlighted some specific changes in vascular parameters with aging. The rising edge could be considered as one parameter in determining the age-dependent vascular state.

Vascular Health and Cognitive Function in Older Adults with Cardiovascular Disease

BACKGROUND: We hypothesized that changes in vascular flow dynamics resulting from age and cardiovascular disease (CVD) would correlate to neurocognitive capacities, even in adults screened to exclude dementia and neurological disease. We studied endothelial-dependent as well as endothelial-independent brachial responses in older adults with CVD to study the associations of vascular responses with cognition. Comprehensive neurocognitive testing was used to discern which specific cognitive domain(s) correlated to the vascular responses. METHODS: Eighty-eight independent, community-dwelling older adults (70.02+7.67 years) with mild to severe CVD were recruited. Enrollees were thoroughly screened to exclude neurological disease and dementia. Flow-mediated (endothelial-dependent) and nitroglycerin-mediated (endothelial-independent) brachial artery responses were assessed using 2-d ultrasound. Cognitive functioning was assessed using comprehensive neuropsychological testing. Linear regression analyses were used to evaluate the relationships between the endothelial-dependent and endothelial-independent vascular flow dynamics and specific domains of neurocognitive function. RESULTS: Endothelial-dependent and endothelial-independent brachial artery responses both correlated with neurocognitive testing indices. The strongest independent relationship was between endothelial function and measures of attention-executive functioning. CONCLUSIONS: Endothelial-dependent and endothelial-independent vascular responsiveness correlate with neurocognitive performance among older CVD patients, particularly in the attention-executive domain. While further study is needed to substantiate causal relationships, our data demonstrate that brachial responses serve as important markers of risk for common neurocognitive changes. Learning and behavior-modifying therapeutic strategies that compensate for such common, insidious neurocognitive limitations will likely improve caregiving efficacy.

Chronic treatment with N-acetyl-cystein delays cellular senescence in endothelial cells isolated from a subgroup of atherosclerotic patients

Endothelial senescence may contribute to the pathogenesis of age-related vascular disorders. Furthermore, chronic exposure to risk factors for cardiovascular disease (CVD) accelerates the effects of chronological aging by generating stress-dependent damages, including oxidative stress, therefore promoting stress-induced premature senescence. Our objective was to determine whether a chronic treatment with an antioxidant (N-acetyl-cystein, NAC) could delay senescence of endothelial cells (EC) isolated and cultured from arterial segments of patients with severe coronary artery disease. If EC were considered as one population (n=26), chronic NAC treatment slightly shortened telomere attrition rate associated with senescence but did not significantly delay the onset of endothelial senescence. However, in a subgroup of NAC-treated EC (n=15) cellular senescence was significantly delayed, NAC decreased lipid peroxidation (HNE), activated the catalytic subunit of telomerase (hTERT) and inhibited telomere attrition. In contrast, in another subgroup of EC (n=11) characterized by initial short telomeres, no effect of NAC on HNE and high levels of DNA damages, the antioxidant was not beneficial on senescence, suggesting an irreversible stress-dependent damage. In conclusion, chronic exposure to NAC can delay senescence of diseased EC via hTERT activation and transient telomere stabilization, unless oxidative stress-associated cell damage has become irreversible.

Influence of cardiac-specific overexpression of insulin-like growth factor 1 on lifespan and aging-associated changes in cardiac intracellular Ca2+ homeostasis, protein damage and apoptotic protein expression

A fall in circulating levels of cardiac survival factor insulin-like growth factor 1 (IGF-1) contributes to cardiac aging. To better understand the role of IGF-1 in cardiac aging, we examined the influence of cardiac IGF-1 overexpression on lifespan, cardiomyocyte intracellular Ca2+ homeostasis, protein damage, apoptosis and expression of pro- and anti-apoptotic proteins in young and old mice. Mouse survival rate was constructed by the Kaplan-Meier curve. Intracellular Ca2+ was evaluated by fura-2 fluorescence. Protein damage was determined by protein carbonyl formation. Apoptosis was assessed by caspase-8 expression, caspase-3 and TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling) assay. Pro- and anti-apoptotic proteins including Bax, p53, pp53, Bcl2, Omi/HtrA2, apoptosis repressor with caspase recruitment domain (ARC) and X-linked inhibitor of apoptosis protein (XIAP) were assessed by Western blot. Aging decreased plasma in IGF-1 levels, elevated myocyte resting intracellular Ca2+ levels, reduced electrically stimulated rise in intracellular Ca2+ and delayed intracellular Ca2+ decay associated with enhanced protein carbonyl formation, caspase-8 expression and caspase-3 activity in FVB mice, all of which with the exception of elevated resting intracellular Ca2+ were attenuated by IGF-1. Aging up-regulated expression of Bax, Bcl2 and ARC, down-regulated XIAP expression and did not affect p53, pp53 and Omi/HtrA2. The IGF-1 transgene attenuated or nullified aging-induced changes in Bax, Bcl2 and XIAP. Our data suggest a beneficial role for IGF-1 in aging-induced survival, cardiac intracellular Ca2+ homeostasis, protein damage and apoptosis possibly related to pro- and anti-apoptotic proteins.

Procedural results and acute complications in stenting native and recurrent coarctation of the aorta in patients over 4 years of age: a multi-institutional study

BACKGROUND

We report a multi-institutional experience with intravascular stenting (IS) for treatment of coarctation of the aorta.

METHODS AND RESULTS

Data was collected retrospectively by review of medical records from 17 institutions. The data was broken down to prior to 2002 and after 2002 for further analysis. A total of 565 procedures were performed with a median age of 15 years (mean=18.1 years). Successful reduction in the post stent gradient (<20 mm Hg) or increase in post stent coarctation to descending aorta (DAo) ratio of >0.8 was achieved in 97.9% of procedures. There was significant improvement (P<0.01) in pre versus post stent coarctation dimensions (7.4 mm+/-3.0 mm vs. 14.3+/-3.2 mm), systolic gradient (31.6 mm Hg+/-16.0 mm Hg vs. 2.7 mm Hg+/-4.2 mm Hg) and ratio of the coarctation segment to the DAo (0.43+/-0.17 vs. 0.85+/-0.15). Acute complications were encountered in 81/565 (14.3%) procedures. There were two procedure related deaths. Aortic wall complications included: aneurysm formation (n=6), intimal tears (n=8), and dissections (n=9). The risk of aortic dissection increased significantly in patients over the age of 40 years. Technical complications included stent migration (n=28), and balloon rupture (n=13). Peripheral vascular complications included cerebral vascular accidents (CVA) (n=4), peripheral emboli (n=1), and significant access arterial injury (n=13). Older age was significantly associated with occurrence of CVAs. A significant decrease in the technical complication rate from 16.3% to 6.1% (P<0.001) was observed in procedures performed after January 2002.

CONCLUSIONS

Stent placement for coarctation of aorta is an effective treatment option, though it remains a technically challenging procedure. Technical and aortic complications have decreased over the past 3 years due to, in part, improvement in balloon and stent design. Improvement in our ability to assess aortic wall compliance is essential prior to placement of ISs in older patients with coarctation of the aorta.

Effect of unilateral resistance training on arterial compliance in elderly men

An increase in age coincides with a decrease in arterial compliance, which is related to a higher risk for cardiovascular accidents. Evidence regarding the effects of resistance training on arterial compliance is conflicting. Currently, little information is available about the effect of resistance training on arterial compliance in elderly men. We assessed the impact of 10 weeks of unilateral arm and leg resistance training on carotid, brachial, and femoral arterial compliance in 12 healthy elderly men (mean age ± SD, 71 ± 7 y). Arterial compliance was evaluated before, after 4 weeks, and after 10 weeks of unilateral resistance training by simultaneously measuring arterial diameter and blood pressure in each artery. There were no significant differences in arterial compliance or stiffness index in any of the arteries examined after 10 weeks of training. However, after 10 weeks of resistance training, resting heart rate decreased from 76 ± 4 beats/min to 61 ± 3 beats/min (p < 0.05), plasma glucose decreased from 6.0 ± 0.9 to 5.1 ± 0.9 mmol/L (mean ± SE) (p < 0.05), and carotid artery peak blood flow increased from 1831 mL/min to 2245 mL/min (p < 0.05). There were no significant changes in resting arterial blood pressure. Unilateral resistance training for 10 weeks does not alter peripheral and central arterial compliance elderly men.

Uniaxial stretch-induced regulation of mitogen-activated protein kinase, Akt and p70 S6 kinase in the ageing Fischer 344 x Brown Norway rat aorta

The effects of ageing on the cardiovascular system contribute to substantial alterations in cellular morphology and function. The variables regulating these changes are unknown; however, one set of signalling molecules that may be of particular importance in mediating numerous cellular responses, including control of cell growth, differentiation and adaptation, are the proteins associated with the mitogen-activated protein kinase (MAPK) signalling systems. The MAPKs, in conjunction with the p70 S6k signalling cascade, have emerged as critical components for regulating numerous mechanotransduction-related cellular responses. Here we investigate the ability of uniaxial stretch to activate the MAPK and p70 S6k pathways in adult (6-month-old), aged (30-month-old) and very aged (36-month-old) Fischer 344/NNiaHSd x Brown Norway/BiNia (FBN) rats. Western blotting of the MAPK family proteins extracellular signal-regulated kinase (Erk) 1/2, p38- and c-Jun NH(2)-terminal kinase (Jnk)-MAPKs showed differential expression and activation between these proteins with age. An acute 15 min interval of 20% uniaxial stretch using an ex vivo aortic preparation demonstrated similar regulation of Erk1/2, p38- and Jnk-MAPK. However, ageing altered uniaxial induced p70 S6k pathway signalling. These observations confirm previous data demonstrating that MAPK proteins are mechanically regulated and also suggest that p70 S6k signalling expression and activation are controlled differently with ageing. Taken together, these data may help to explain, in part, the age-related changes in vascular morphology, function and response to injury.

Antioxidative effects of plant polyphenols: from protection of G protein signaling to prevention of age-related pathologies

The antioxidant potency of three natural polyphenols, resveratrol, curcumin, and genistein, was compared by using the two human models: oxymodified with H(2)O(2) and homocysteine (Hcy) G proteins in the postmortem frontal cortex (FC) membranes of age-matched control and Alzheimer's disease (AD) subjects; and Cu(2+)-induced oxidation of plasma low-density lipoproteins (LDL). In Co, 3-10 microM polyphenols dose-dependently depressed the G protein 25% stimulation induced by 10 microM H(2)O(2) or 500 microM Hcy. Resveratrol revealed significantly higher antioxidativity than curcumin or genistein. In AD, the antioxidativity of polyphenols showed no significant differences. Polyphenols (1 microM) significantly increased the LDL oxidation lag time (oxyresistance) as compared with control, the effect of resveratrol being most potent. Due to the dual antioxidant mechanism, the investigated polyphenols, particularly resveratrol, should have preferences for the preventive-therapeutic use in age-related oxidative stress-based pathologies.

Ten commandments for the future of ageing research in the UK: a vision for action

Increases in longevity resulting from improvements in health care and living conditions together with a decrease in fertility rates have contributed to a shift towards an aged population profile. For the first time the UK has more people over age 60 than below 16 years of age. The increase in longevity has not been accompanied by an increase in disease-free life expectancy and research into ageing is required to improve the health and quality of life of older people. However, as the House of Lords reported, ageing research in the UK is not adequately structured and a clear vision and plan are urgently required. Hence, with the aim of setting a common vision for action in ageing research in the UK, a 'Spark Workshop' was organised. International experts from different disciplines related to ageing research gathered to share their perspectives and to evaluate the present status of ageing research in the UK. A detailed assessment of potential improvements was conducted and the prospective secondary gains were considered, which were subsequently distilled into a list of 'ten commandments'. We believe that these commandments, if followed, will help to bring about the necessary implementation of an action plan for ageing research in the UK, commensurate with the scale of the challenge, which is to transform the manifold opportunities of increased longevity into actual delivery of a society living not only for longer, but also healthier, wealthier and happier.

Age-related changes in echocardiographic measurements: association with variation in the estrogen receptor-alpha gene

Left ventricular (LV) mass and other LV measures have been shown to be heritable. In this study we hypothesized that functional variation in the gene coding for estrogen receptor-alpha (ESR1), known for mediating the effect of estrogens on myocardium, is associated with age-related changes in LV structure. Four genetic markers (ESR1 TA repeat; rs2077647, or +30T>C; rs2234693, or PvuII; and rs9340799, or XbaI) were genotyped in 847 unrelated individuals (488 women) from the Framingham Offspring Study, who attended 2 examination cycles 16 years apart (mean ages at first examination: 43+/-9 years; at follow-up: 59+/-9 years). ANCOVA was used to assess the association of polymorphisms and their haplotypes with cross-sectional measurements and longitudinal changes in LV mass, wall thickness, end-diastolic and end-systolic internal diameter, and fractional shortening after adjustment for factors known to influence these variables. Changes over time were detected for all of the LV measurements (P ranging from <0.0001 to 0.02), except for fractional shortening in men. The SS genotype of the ESR1 TA repeat polymorphism in the promoter region was associated with longitudinal changes in LV mass and LV wall thickness (P ranging from 0.0006 to 0.01). Moreover, the TA[S]-+30[T]-PvuII[T]-XbaI[A] haplotype (frequency: 47.5%) was associated with greater LV changes as compared with the TA[L]-+30[C]-PvuII[C]-XbaI[G] haplotype (frequency: 31.8%). Our results are consistent with the hypothesis that common ESR1 polymorphisms are significantly associated with age-related changes in LV structure. Understanding the mechanisms predisposing to unfavorable LV remodeling of the heart with advancing age may aid in the discovery of new therapeutic targets for the prevention of heart failure.

KCNQ potassium channel mutations cause cardiac arrhythmias in Drosophila that mimic the effects of aging

Population profiles of industrialized countries show dramatic increases in cardiovascular disease with age, but the molecular and genetic basis of disease progression has been difficult to study because of the lack of suitable model systems. Our studies of Drosophila show a markedly elevated incidence of cardiac dysfunction and arrhythmias in aging fruit fly hearts and a concomitant decrease in the expression of the Drosophila homolog of human KCNQ1-encoded K(+) channel alpha subunits. In humans, this channel is involved in myocardial repolarization, and alterations in the function of this channel are associated with an increased risk for Torsades des Pointes arrhythmias and sudden death. Hearts from young KCNQ1 mutant fruit flies exhibit prolonged contractions and fibrillations reminiscent of Torsades des Pointes arrhythmias, and they exhibit severely increased susceptibility to pacing-induced cardiac dysfunction at young ages, characteristics that are observed only at advanced ages in WT flies. The fibrillations observed in mutant flies correlate with delayed relaxation of the myocardium, as revealed by increases in the duration of phasic contractions, extracellular field potentials, and in the baseline diastolic tension. These results suggest that K(+) currents, mediated by a KCNQ channel, contribute to the repolarization reserve of fly hearts, ensuring normal excitation-contraction coupling and rhythmical contraction. That arrhythmias in both WT and KCNQ1 mutants become worse as flies age suggests that additional factors are also involved.

Postural differences in hemodynamics and diastolic function in healthy older men

The shift from upright to supine posture increases stroke volume in healthy young adults, primarily through increased end-diastolic volume. Aging is associated with increased ventricular stiffness and impaired diastolic function. The purpose of this study was to determine whether the stroke volume change between the upright and supine posture was blunted in healthy older men and whether the early mitral inflow response to this postural change was reduced by aging. Pulsed Doppler echocardiography and tissue Doppler imaging were used to assess stroke volume and left ventricular function during upright and supine posture in 10 young and 12 older healthy men. Cardiac output was greater in the supine versus upright condition in both groups. In young men supine posture was associated with a large increment in stroke volume (63.1 +/- 7.2 upright to 98.6 +/- 11.7 ml supine; P < 0.05) and a decrease in heart rate. In older men, the stroke volume increment was smaller (63.9 +/- 3.6 upright to 82.0 +/- 5.7 ml supine; P < 0.05) and heart rate decreased less than young men when comparing upright to supine posture. Increased stroke volume was associated with higher peak early diastolic filling velocity (E) in young men and higher peak late diastolic filling velocity (A) in older men. These findings indicate that healthy aging attenuates the increase in early filling associated with moving from an upright to a supine posture. Furthermore, healthy older men are more dependent upon atrial diastolic filling to augment end-diastolic and stroke volume, which may be due to age-associated increases in left ventricular filling pressure and impaired compliance.

Effect of gender on blood flow velocities and blood pressure: role of body weight and height

Aging and gender alter arterial hemodynamic function. Gender-related differences in body size may affect the arterial hemodynamics such as systolic blood pressure, wave reflection and pressure wave propagation. To assess the possibility that the differences of carotid blood velocities and brachial blood pressure in women are related to body size, we investigated the arterial hemodynamics in 50 healthy young adults (30 men, 20 women) between the age ranges of 20 to 29 years old. Blood velocities are characterized to 5 components of velocity waveforms as peak systolic (S1), second systolic (S2), incisura between systole and diastole (I), peak diastolic (D) and end-diastolic velocity wave (d). As the most pronounced systolic blood pressure is lower in young women than men (P<0.05). Women have higher diastolic velocity components and second systolic velocity, but have lower systolic velocity compared to men. From that, women have a significant greater wave reflection, smaller vascular resistive and lower vascular elastic recoil than in men. Greater body weight is associated with higher blood pressures (P<0.05) and lower blood velocities (P<0.05). Shorter body height affects not only the increased velocity wave reflection index (r= -0.519, P>0.0001), but also the decrease of peripheral vascular resistive index (RI) and arterial vascular elastic recoil index (r= 0.463, P<0.0001; r= 0.481, P<0.0001, respectively). In conclusion, body size influences blood pressure and velocity regulations in the young population.

Effects of aging and exercise training on the common carotid blood velocities in healthy men

An age-related alteration in the cardiovascular response to exercise training are evident. The purpose of the study was to investigate the effects of exercise and age on blood velocities in common carotid artery in 82 healthy men between the age ranges of 21 to 67 years old. Blood velocities are characterized to five components of velocity waveforms as peak systolic (S1), second systolic (S2), incisura between systole and diastole (I), peak diastolic (D) and end-diastolic velocity wave (d). Decrease of blood velocities in peak systolic (r= -0.711, P<0.0001) and in peak diastolic velocities (r= -0.521, P<0.0001) with aging are improved and partially restore in particularly older men. The velocity ratio of S2/S2-1 as a reflection index increase with age (r= 0.797, P<0.0001), however is smaller in exercise-trained older compared with sedentary peers. The ratio of 1-I/D as a vascular elastic recoil index decrease with aging (r= -0.640, P<.0001), but is relatively higher in exercise-trained men. Exercise training improves the age-related deterioration in blood velocities and its indices in healthy men. In the further investigations, the assessment of aerobic fitness and vascular aging has potential by using the criteria of peak systolic and peak diastolic, and its indices.

Change of serum albumin and risk of cardiovascular disease and all-cause mortality: Longitudinal Aging Study Amsterdam

The aim of this longitudinal study was to investigate 3-year change in serum albumin concentration as a determinant of incident cardiovascular disease (CVD) and all-cause mortality. Data were from 713 respondents of the Longitudinal Aging Study Amsterdam initially aged 55-85 years. Serum albumin was measured at baseline (1992/1993) and after 3 years. At the 6-year follow-up, incident CVD (among 456 respondents with no prevalent CVD at the 3-year follow-up) and all-cause mortality were ascertained. Overall, 18.9% developed CVD and 10.9% died. After adjustment for potential confounders, a higher level of serum albumin at the 3-year follow-up was associated with a lower risk for incident CVD (relative risk = 0.88, 95% confidence interval (CI): 0.79, 0.98). The risk of incident CVD was 0.88 (95% CI: 0.78, 0.99) per unit (g/liter) increase in change in albumin between 3-year follow-up and baseline. Chronic low serum albumin (<or=43 g/liter at baseline and 3-year follow-up) was not associated with incident CVD (p = 0.22). A clinically relevant decrease in serum albumin (>or=1 standard deviation (2.5 g/liter) between baseline and 3-year follow-up) tended to be associated with a twofold risk (relative risk = 2.00, 95% CI: 0.91, 4.39). For all-cause mortality, no associations were observed. These findings suggest that older persons with a decrease in serum albumin concentration, even within the normal range, might be at increased risk of incident CVD. Change in serum albumin may be used as an early marker for CVD risk.

Management of the critically ill geriatric patient

OBJECTIVE

To review the effect of an aging society on the utilization of critical care services and the physiology of aging as it applies to critical illness and prognosis and management issues in the intensive care unit (ICU).

DATA SOURCE

MEDLINE, Embase, and citation review of relevant primary and review articles.

DATA SYNTHESIS

Elderly patients (age of >65 yrs) currently account for 42-52% of ICU admissions and for almost 60% of all ICU days. Aging is associated with decreased cardiopulmonary and renal reserve and with a high rate of co-morbidities, increasing the risks of the elderly developing progressive organ failure. Elderly ICU patients are at a particularly high risk of developing delirium, which is associated with significant morbidity. Severity of illness and age are the important factors determining ICU survival. Age and functional status before ICU admission are the major determinants of survival at 6 and 12 months after ICU discharge. Age alone should not be used to triage ICU patients; the decision to admit an elderly patient to an ICU should be based on the patients co-morbidities, acuity of illness, prehospital functional status, and preferences with regard to life-sustaining treatment.

CONCLUSIONS

The management of critically ill elderly patients is a complex issue and involves an understanding of the changing demographics of our society and the physiology of aging. The reality of our aging society dictates that we must focus on how to best care for the elderly who develop critical illness.

Effects of leg resistance training on arterial function in older men

BACKGROUND

Little information is available on the effect of strength training on vascular function, particularly in older people.

OBJECTIVE

To determine the effect of resistance training on arterial stiffness and endothelial function in older adults.

METHOD

Eleven healthy men (mean (SEM) age 64 (1) years) performed 12 weeks of resistance training involving knee flexion and extension (three sets a day, two days a week).

RESULTS

Resistance training increased maximal muscle power by 16% (p<0.0001). Arterial stiffness as assessed by aortic pulse wave velocity did not change with resistance training. Plasma concentration of nitric oxide (NO), measured as its stable end product (nitrite/nitrate), had increased (p<0.05) after resistance training (61.2 (10.4) v 39.6 (3.2) micromol/l). There was no change in plasma concentration of endothelin-1.

CONCLUSION

The results suggest that short term resistance training may increase NO production without stiffening central arteries in healthy older men.

Age and flow-mediated dilation: a comparison of dilatory responsiveness in the brachial and popliteal arteries

Previous investigations of age-associated changes in flow-mediated vasodilation (FMD) in women have been limited to the upper extremity and have not accounted for possible age differences in the stimulus for dilation. The purpose of the present study was to compare age differences in brachial and popliteal FMD and its stimulus (changes in shear rate following occlusion). Ultrasound-derived diameters and Doppler flow velocities of the brachial and popliteal arteries were measured in 14 young (20- to 30-yr-old) and 14 older (60- to 79-yr-old) healthy women at rest and during and after 5 min of distal cuff occlusion. Resting diameters were similar (both P > 0.39) in both age groups. Peak shear rate did not differ with age in either artery: approximately 1,300-1,400 and approximately 400-500 s(-1) in brachial and popliteal arteries, respectively. FMD (percent change above diameter measured during occlusion) was approximately 50-60% lower (P < 0.05) in the brachial (15.8 + 0.8% vs. 8.1 + 1.5%) and popliteal (4.6 +/- 0.7% vs. 1.8 +/- 0.4%) arteries of the older women. The normalized response of the brachial and popliteal arteries (%FMD per unit change in shear rate) was also reduced with age (55% and 53%, respectively) but did not exhibit limb specificity. Additionally, endothelium-independent dilation, as assessed by administration of nitroglycerin, was similarly blunted (by 45-65%) in brachial and popliteal arteries of older women. These results suggest that 1) brachial and popliteal artery FMD (after 5 min of distal occlusion) are similarly reduced with age, 2) when normalized to the change in shear stimulus, both arteries are equally responsive to 5 min of distal cuff occlusion in women, and 3) the age-associated decline in FMD may be attributable in part to diminished smooth muscle responsiveness.

Motor plasticity in a juggling task in older adults-a developmental study

OBJECTIVE

to examine the plasticity of motor performance in old age. Older adults were instructed and trained in a juggling task and their performances were compared, first, within the group of older adults and, second, with the performances of children, youths and younger adults.

SUBJECTS

older adults, children, youths and younger adults (n = 1,206, range 6-89 years).

METHODS

participants were asked to learn a juggling task. Performance was tested before semantic instruction (pre-test 1), after semantic instruction (pre-test 2) and after 6 days of juggling practice (post-test). None of the participants had prior experiences in juggling. Results were analysed using repeated measure analysis of variance (ANOVA).

RESULTS

older adults showed a clear improvement in juggling performance after instruction and after six training sessions. On average, they reached performances comparable with those of children aged between 10 and 14 years, and with those of younger adults aged between 30 and 59 years. Only youths and younger adults aged between 15 and 29 years showed significantly higher performances at baseline, after instruction and after training.

CONCLUSIONS

older adults exhibit high reserve capacity, that is, a potential for learning 'new' motor skills.

Aging alters vascular mechanotransduction: pressure-induced regulation of p70S6k in the rat aorta

Physical forces are important regulators of vascular structure and function though it is unknown how aging may affect the ability of the vasculature to respond to mechanical stimuli. We investigated the pressure-induced activation of ribosomal S6-kinase (p70S6k) and its pathway-related proteins (Akt, GSK-3beta, SHP-2, PTEN) in aortae from young adult (6 month), aged (30 month), and very aged (36 month) Fischer 344 x Brown Norway F1 hybrid rats. With aging, the aortic tissue content of Akt. SHP-2, and PTEN was significantly increased while total p70S6k and GSK-3beta were unchanged. By comparison, the basal phosphorylation of p70S6k at Thr 389 and Thr 421/Ser 424 was increased ( approximately 40%) and unchanged, respectively, while Akt decreased (approximately 37%), GSK-3beta was unchanged, SHP-2 increased (approximately 73.5%), and PTEN increased (approximately 120%) in the aortae of very aged rats. Acute pressurization of aortae resulted in similar increases in phosphorylation of Akt among the different age groups. By comparison, pressure-induced phosphorylation of p70S6k at Thr 389, GSK-3beta and SHP-2 decreased; whereas, PTEN dephosphorylation was increased in 36-month versus 6-month aortae. The results indicate marked alterations in the p70S6k signaling pathway with aging. The implications of these findings on age-associated vessel remodeling are discussed.

A patient-specific computational model of fluid–structure interaction in abdominal aortic aneurysms

It is generally believed that knowledge of the wall stress distribution could help to find better rupture risk predictors of abdominal aortic aneurysms (AAAs). Although AAA wall stress results from combined action between blood, wall and intraluminal thrombus, previously published models for patient-specific assessment of the wall stress predominantly did not include fluid-dynamic effects. In order to facilitate the incorporation of fluid-structure interaction in the assessment of AAA wall stress, in this paper, a method for generating patient-specific hexahedral finite element meshes of the AAA lumen and wall is presented. The applicability of the meshes is illustrated by simulations of the wall stress, blood velocity distribution and wall shear stress in a characteristic AAA. The presented method yields a flexible, semi-automated approach for generating patient-specific hexahedral meshes of the AAA lumen and wall with predefined element distributions. The combined fluid/solid mesh allows for simulations of AAA blood dynamics and AAA wall mechanics and the interaction between the two. The mechanical quantities computed in these simulations need to be validated in a clinical setting, after which they could be included in clinical trials in search of risk factors for AAA rupture.

Assessment of age-related changes in left ventricular structure and function by freehand three-dimensional echocardiography

To determine age-related changes in left ventricular (LV) structure and function, the authors used freehand three-dimensional echocardiography, a previously validated tomographic technique, to measure LV mass, volumes, and derived parameters in 94 sedentary, but ambulatory and clinically healthy, adult male and female volunteers aged 20-94. LV volumes and mass were significantly greater in men than in women (p<0.001) and remained greater after adjustment for body surface area and height (p<0.05). Declines in end-diastolic and stroke volumes with age were reduced or absent after accounting for body size. By multivariate analysis, age accounted for only about 6%-11% of the variance among LV volumes and mass, in comparison with body surface area and gender, which accounted jointly for about 46%-77% of the variance. In conclusion, changes occur in LV structure and function with normal aging, but these changes are relatively minor when body size and gender are taken into account.

Ageing and activity: their effects on the functional reserve capacities of the heart and vascular smooth and skeletal muscles

During perinatal life striated muscles grow through the acquisition of more contractile cells (myocytes or fibres) followed by their postnatal enlargement (i.e. hypertrophy). In the ageing adult these events are reversed, with a progressive loss of myocytes that cannot be fully compensated despite the presence of cell renewal systems or reactive myocyte hypertrophy. Hence the functional reserve capacities of the heart and skeletal muscles decline with age. This is probably a consequence of physiological ageing and diminished levels of physical activity. As a result daily tasks once taken for granted become progressively more difficult, and eventually impossible, to perform. For example, sufficient coordinated absolute muscle force is required for an individual to rise from a chair or climb stairs, and the reserve capacity of the heart is a major determinant of an individual's ability to remain active and cope with daily stresses and illnesses. Long-term participation in endurance-based activities helps to preserve cardiac reserve, and has both direct and indirect beneficial effects on vascular smooth muscle and health preservation within the cardiovascular system. In contrast, this type of activity does little to protect skeletal muscles against the age-related losses of fast-twitch fibres, small motor units, overall muscle mass and power output. While resistance exercise promotes fibre hypertrophy in skeletal muscles, and to a lesser extent in myocytes of the heart, the explosive power of muscles still declines with age. Hence, while physical activity is important in attenuating age-related changes in muscle function and its reserve capacity, it delays rather than prevents the deleterious effects of ageing per se. Despite this, in a culture where inactivity has become an accepted part of life we still need to explore in greater detail the benefits of habitual physical activity, and use this information as a community-based educational tool to help prevent or delay cardiovascular disease, obesity, arthritis and the frailty associated with old age.

Myocardial substrate metabolism in the normal and failing heart

The alterations in myocardial energy substrate metabolism that occur in heart failure, and the causes and consequences of these abnormalities, are poorly understood. There is evidence to suggest that impaired substrate metabolism contributes to contractile dysfunction and to the progressive left ventricular remodeling that are characteristic of the heart failure state. The general concept that has recently emerged is that myocardial substrate selection is relatively normal during the early stages of heart failure; however, in the advanced stages there is a downregulation in fatty acid oxidation, increased glycolysis and glucose oxidation, reduced respiratory chain activity, and an impaired reserve for mitochondrial oxidative flux. This review discusses 1) the metabolic changes that occur in chronic heart failure, with emphasis on the mechanisms that regulate the changes in the expression of metabolic genes and the function of metabolic pathways; 2) the consequences of these metabolic changes on cardiac function; 3) the role of changes in myocardial substrate metabolism on ventricular remodeling and disease progression; and 4) the therapeutic potential of acute and long-term manipulation of cardiac substrate metabolism in heart failure.

Aortic Input Impedance Increases With Age in Healthy Men and Women

Aortic input impedance represents the hydraulic load presented by the systemic circulation to the left ventricle of the heart and is increased in patients with cardiovascular disease. Aging is a strong independent risk factor for cardiovascular disease and could exert this effect partly through an increase in modulus of aortic input impedance. We used a novel noninvasive technique to determine aortic input impedance in 71 healthy men and women aged 20 to 69 years. We found that the aortic input impedance spectrum was shifted rightward with advancing age, characterized by a 37% increase in the frequency of the minimum modulus between the third and seventh decade (P<0.0001). The frequency of the minimum modulus correlated with age in all subjects (r=0.48; P<0.0001), in men (r=0.43; P<0.005), and in women (r=0.53; P=0.001). Although several physical characteristics were associated with the frequency of the minimum modulus (bivariate correlation), a regression model that included age and these physical characteristics showed that age was the only independent predictor of the frequency of the minimum modulus. We conclude that aortic input impedance increases with advancing age in healthy men and women. This increase in aortic input impedance may be an important mechanism by which age increases the risk of cardiovascular disease in humans.

Tempol improves vascular function in the mesenteric vascular bed of senescent rats

Ageing is associated with structural and functional alterations of the vasculature. The nature of age-related vascular disorders is not completely understood. Oxidative stress is hypothesized to play a crucial role in the pathophysiology of vascular complications. We investigated the effects of chronic treatment with the superoxide dismutase mimetic tempol (4-hydroxy-2,2,6,6-tetramethyl piperidinoxyl) on vascular function in the mesenteric vasculature of aged rats. Young (3 weeks) and old (40 weeks) Sprague-Dawley rats were treated with tempol (1 mM in drinking water) or vehicle for 3 weeks. Arterial blood pressure was slightly, but significantly, higher in old than in young rats. Tempol had no effect on arterial blood pressure. The vasoconstrictor responses to norepinephrine (NE) and serotonin (5-HT) were exaggerated in the mesenteric vascular bed (MVB) removed from old rats. Vasodilator responses to acetylcholine (ACh), papaverine (PPV), and isoprenaline (ISO) were reduced in the MVB of old rats in comparison with young rats. Chronic treatment of old rats with tempol normalized their responses to NE and 5-HT. The dilator responses to ACh, PPV, and ISO were similar between old rats receiving tempol and young rats. The present findings suggest that oxidative stress contributes to vascular dysfunction in the mesentery of old rats. The vasculoprotective effects of tempol remain to be elucidated.

Increased nitration of sarcoplasmic reticulum Ca2+-ATPase in human heart failure

BACKGROUND

Reduced sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA2a isoform) activity is a major determinant of reduced contractility in heart failure. Ca2+-ATPase inactivation can occur through SERCA2a nitration. We therefore investigated the role of SERCA2a nitration in heart failure.

METHODS AND RESULTS

We measured SERCA2a levels and nitrotyrosine levels in tissue from normal and failing human hearts using Western blots. We found that nitrotyrosine levels in idiopathic dilated cardiomyopathic (DCM) hearts were almost double those of control hearts in age-matched groups. Nitrotyrosine was dominantly present in a single protein with the molecular weight of SERCA2a, and immunoprecipitation confirmed that the protein recognized by the nitrotyrosine antibody was SERCA2a. There was a positive correlation between the time to half relaxation and the nitrotyrosine/SERCA2a content (P<0.01) in myocytes isolated from control and DCM hearts. In experiments with isolated SR vesicles from porcine hearts, we also showed that the Ca pump is inactivated by peroxynitrite exposure, and inactivation was prevented by protein kinase A pretreatment.

CONCLUSIONS

We conclude that SERCA2a inactivation by nitration may contribute to Ca pump failure and hence heart failure in DCM.

Effect of aging and physical activity on left ventricular compliance

BACKGROUND

Left ventricular compliance appears to decrease with aging, which may contribute to the high incidence of heart failure in the elderly. However, whether this change is an inevitable consequence of senescence or rather secondary to reduced physical activity is unknown.

METHODS AND RESULTS

Twelve healthy sedentary seniors (69.8+/-3 years old; 6 women, 6 men) and 12 Masters athletes (67.8+/-3 years old; 6 women, 6 men) underwent pulmonary artery catheterization to define Starling and left ventricular pressure-volume curves. Data were compared with those obtained in 14 young but sedentary control subjects (28.9+/-5 years old; 7 women, 7 men). Pulmonary capillary wedge pressures and left ventricular end-diastolic volumes by use of echocardiography were measured at baseline, during decreased cardiac filling by use of lower-body negative pressure (-15 and -30 mm Hg), and after saline infusion (15 and 30 mL/kg). Stroke volume for any given filling pressure was greater in Masters athletes compared with the age-matched sedentary subjects, whereas contractility, as assessed by preload recruitable stroke work, was similar. There was substantially decreased left ventricular compliance in healthy but sedentary seniors compared with the young control subjects, which resulted in higher cardiac pressures for a given filling volume and higher myocardial wall stress for a given strain. The pressure-volume curve for the Masters athletes was indistinguishable from that of the young, sedentary control subjects.

CONCLUSIONS

A sedentary lifestyle during healthy aging is associated with decreased left ventricular compliance, leading to diminished diastolic performance. Prolonged, sustained endurance training preserves ventricular compliance with aging and may help to prevent heart failure in the elderly.

Parvalbumin gene delivery improves diastolic function in the aged myocardium in vivo

Abnormal relaxation of the heart, termed diastolic dysfunction, is a significant and growing problem that is a major cause of heart failure in the aged population. The potential of gene transfer of parvalbumin (Parv), a cytoplasmic calcium-binding protein, to improve diastolic function in the aged myocardium in vivo was evaluated. Despite evidence for an early developmental influence on the efficiency of Ad5 striated muscle transduction, results show that Ad5 gene transfer efficiency to adult cardiac myocytes in vitro is identical in young and old rats, suggesting that the basic processes of adenovirus binding and internalization are unaffected by aging. In contrast, Ad5-mediated Parv gene transfer to the myocardium in vivo is reduced in old rats compared to young rats. Nonetheless, Parv gene transfer and expression in vivo were sufficient to improve tau, a load-independent indicator of diastolic function, assessed using catheter-based micromanometry in the aged myocardium. These results suggest that expression of the calcium buffer Parv may represent an effective approach to functional correction of the failing heart in the aging.

Myocardial aging and senescence: where have the stem cells gone?

Heart failure remains a leading cause of hospital admissions and mortality in the elderly, and current interventional approaches often fail to treat the underlying cause of pathogenesis. Preservation of structure and function in the aging myocardium is most likely to be successful via ongoing cellular repair and replacement, as well as survival of existing cardiomyocytes that generate contractile force. Research has led to a paradigm shift driven by application of stem cells to generate cardiovascular cell lineages. Early controversial findings of pluripotent precursors adopting cardiac phenotypes are now widely accepted, and current debate centers upon the efficiency of progenitor cell incorporation into the myocardium. Much work remains to be done in determining the relevant progenitor cell population and optimizing conditions for efficient differentiation and integration. Significant implications exist for treatment of pathologically damaged or aging myocardium since future interventional approaches will capitalize upon the use of cardiac stem cells as therapeutic reagents.

Ascorbic acid does not affect large elastic artery compliance or central blood pressure in young and older men

Large elastic artery compliance is reduced and arterial blood pressure (BP) is increased in the central (cardiothoracic) circulation with aging. Reactive oxygen species may tonically modulate central arterial compliance and BP in humans, and oxidative stress may contribute to adverse changes with aging. If so, antioxidant administration may have beneficial effects. Young (Y; 26 +/- 1 yr, mean +/- SE) and older (O; 63 +/- 2 yr, mean +/- SE) healthy men were studied at baseline and during acute (intravenous infusion; Y: n = 13, O: n = 12) and chronic (500 mg/day for 30 days; Y: n = 10, O: n = 10) administration of ascorbic acid (vitamin C). At baseline, peripheral (brachial artery) BP did not differ in the two groups, but carotid artery compliance was 43% lower (1.2 +/- 0.1 vs. 2.1 +/- 0.1 mm(2)/mmHg x 10(-1), P < 0.01) and central (carotid) BP (systolic: 116 +/- 5 vs. 101 +/- 3 mmHg, P < 0.05, and pulse pressure: 43 +/- 4 vs. 36 +/- 3 mmHg, P = 0.16), carotid augmentation index (AIx; 27.8 +/- 7.8 vs. -20.0 +/- 6.6%, P < 0.001), and aortic pulse wave velocity (PWV; 950 +/- 88 vs. 640 +/- 38 cm/s, P < 0.01) were higher in the older men. Plasma ascorbic acid concentrations did not differ at baseline (Y: 71 +/- 5 vs. O: 61 +/- 7 micromol/l, P = 0.23), increased (P < 0.001) to supraphysiological levels during infusion (Y: 1240 +/- 57 and O: 1,056 +/- 83 micromol/l), and were slightly elevated (P < 0.001 vs. baseline) with supplementation (Y: 96 +/- 5 micromol/l vs. O: 85 +/- 6). Neither ascorbic acid infusion nor supplementation affected peripheral BP, heart rate, carotid artery compliance, central BP, carotid AIx, or aortic PWV (all P > 0.26). These results indicate that the adverse changes in large elastic artery compliance and central BP with aging in healthy men are not 1). mediated by ascorbic acid-sensitive oxidative stress (infusion experiments) and 2). affected by short-term, moderate daily ascorbic acid (vitamin C) supplementation.