Influence of Regular Exercise on Age-Related Changes in Arterial Elasticity: Mechanistic Insights From Wall Compositions in Rat Aorta

Arterial stiffness increases with age in healthy sedentary adults. We previously reported that the age-related increases in arterial stiffness are absent or attenuated in regularly exercising adults. However, the mechanism underlying this training effect is unknown. One possibility is that regular exercise minimizes age-related changes in the arterial wall composition of elastin and collagen. To gain insight into this issue, we studied four groups of rats (N = 23): young (42-46 wks) and old (80-84 wks), sedentary and exercise-trained. The exercise group swam 1 hr•d−1, 6 d•wk−1 for 17-21 weeks. There was no significant difference in the incremental elastic modulus between young sedentary and exercise-trained rats. The elastic moduli of the old exercise-trained rats were 31% lower than in the old sedentary controls. As such, the magnitude of age-related increase in the elastic modulus was smaller in the exercise-trained (110%) vs. the sedentary group (151%) (p < 0.05). In both activity groups, elastin content was lower and collagen content was higher in old vs. young rats (p < 0.05). However, there were no significant differences between the two activity groups. These results are not consistent with the hypothesis that regular physical exercise minimizes age-related compositional changes in the arterial wall and attenuates the age-related increase in arterial stiffness. Key words: elastin, collagen, exercise training

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Children and Adolescent Obesity Associates with Pressure-Dependent and Age-Related Increase in Carotid and Femoral Arteries’ Stiffness and Not in Brachial Artery, Indicative of Nonintrinsic Arterial Wall Alteration

International Journal of Vascular Medicine ◽

10.1155/2016/4916246 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 6

Author(s):

Victoria García-Espinosa ◽

Santiago Curcio ◽

Juan Manuel Castro ◽

Maite Arana ◽

Gustavo Giachetto ◽

...

Keyword(s):

Arterial Stiffness ◽

Brachial Artery ◽

Arterial Wall ◽

Statistical Significance ◽

Age Groups ◽

Normal Weight ◽

Children And Adolescent ◽

Age Related ◽

Wall Stiffness ◽

Related Increase

Aim. To analyze if childhood obesity associates with changes in elastic, transitional, and/or muscular arteries’ stiffness.Methods. 221 subjects (4–15 years, 92 females) were assigned to normal weight (NW,n=137) or obesity (OB,n=84) groups, considering their body mass indexz-score. Age groups were defined: 4–8; 8–12; 12–15 years old. Carotid, femoral, and brachial artery local stiffness was determined through systodiastolic pressure-diameter and stress-strain relationships. To this end, arterial diameter and peripheral and aortic blood pressure (BP) levels and waveforms were recorded. Carotid-femoral, femoropedal, and carotid-radial pulse wave velocities were determined to evaluate aortic, lower-limb, and upper-limb regional arterial stiffness, respectively. Correlation analysis between stiffness parameters and BP was done.Results. Compared to NW, OB subjects showed higher peripheral and central BP and carotid and femoral stiffness, reaching statistical significance in subjects aged 12 and older. Arterial stiffness differences disappeared when levels were normalized for BP. There were no differences in intrinsic arterial wall stiffness (elastic modulus), BP stiffness relationships, and regional stiffness parameters.Conclusion. OB associates with BP-dependent and age-related increase in carotid and femoral (but not brachial) stiffness. Stiffness changes would not be explained by intrinsic arterial wall alterations but could be associated with the higher BP levels observed in obese children.

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Effects of Low-Level Cadmium Intake on the Contractility and Morphology of the Rat Aorta

Journal of the American College of Toxicology ◽

10.3109/10915818409009069 ◽

1984 ◽

Vol 3 (1) ◽

pp. 13-24 ◽

Cited By ~ 1

Author(s):

J. L. Hart ◽

E. C. Joyce

Keyword(s):

Drinking Water ◽

Structural Changes ◽

Rat Aorta ◽

Tension Development ◽

Maximum Tension ◽

Low Level ◽

Age Related ◽

Significant Difference ◽

Blood Pressures ◽

Age Related Changes

Female Long Evans hooded rats with an initial mean (± SE) weight of 85.7 ± 1.2 g were exposed to 5 ppm cadmium (Cd) in drinking water for 6 months. Rats which received no Cd in the drinking water served as untreated controls. Weights, systolic blood pressures (tail cuff method), several aspects of aortic ultrastructure, and isolated aortic contractile responses to epinephrine, angiotensin, and potassium chloride at 0, 1, 2, 3, and 6 months were observed in both groups. At none of the testing times was there a significant difference between the weights or systolic blood pressures of the control and Cd-treated groups. Analysis of variance indicated that aortas from control and Cd-treated rats showed similar age-related changes in maximum tension development (contractility) and similar threshold doses. However, Cd-treated aortas developed significantly less maximum tension than control aortas when compared at the same time intervals in response to all of the vasoconstrictors tested. This decreased contractility was apparent at one month and persisted at about the same level (20%) at 2, 3, and 6 months. There were also expected age-related changes in aortic ultrastructure of both groups, and although the 6-month Cd-treated aortas showed more degenerating endothelial cells, differences that might explain the consistent decreases in contractility of the Cd-treated aortas were not observed. The results of this study indicate that chronic low-level Cd treatment causes decreases in aortic contractility, as have previously been reported for acute exposure to Cd, but that this change is not associated with the development of hypertension or with structural changes in the aorta.

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Age-related changes in common carotid arterial stiffness by M-mode echocardiography

Atherosclerosis ◽

10.1016/0021-9150(94)94178-5 ◽

1994 ◽

Vol 109 (1-2) ◽

pp. 294-295

Author(s):

J. Kojima ◽

T. Ushiyama ◽

Y. Kihara

Keyword(s):

Arterial Stiffness ◽

Age Related ◽

Carotid Arterial ◽

Age Related Changes

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Age-related changes in endothelial permeability and distribution volume of albumin in rat aorta

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1993.264.3.h679 ◽

1993 ◽

Vol 264 (3) ◽

pp. H679-H685 ◽

Cited By ~ 7

Author(s):

J. Belmin ◽

B. Corman ◽

R. Merval ◽

A. Tedgui

Keyword(s):

Arterial Wall ◽

Relative Concentration ◽

Endothelial Permeability ◽

Distribution Volume ◽

Albumin Concentration ◽

Macromolecular Transport ◽

Age Related ◽

The Media ◽

Old Rats ◽

Age Related Changes

Age-related changes in macromolecular transport across the arterial wall were investigated in 10-, 20-, and 30-mo-old WAG/Rij rats. Animals were injected with 125I- and 131I-labeled albumin, 90 and 5 min before they were killed, respectively. The transmural distribution of relative concentration of tracers in the aortic wall was obtained using en face serial sectioning technique. The apparent endothelial permeability to albumin calculated from the distribution of 5-min 131I-labeled albumin concentrations was significantly enhanced in 20- and 30-mo-old rats compared with 10-mo-old rats. The apparent distribution volume of albumin within the media, estimated as the mean medial 125I-labeled albumin concentration, was not significantly changed in 20-mo-old rats but was significantly decreased in the 30-mo-old animals. These age-related changes in the macromolecular transport suggest that the entry of plasma macromolecules in the aged arterial wall might be enhanced, whereas the efflux through the media may be impeded, possibly contributing to their trapping in the subendothelium.

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Age-related positivity effect on behavioural responses of dogs to human vocalisations

Scientific Reports ◽

10.1038/s41598-019-56636-z ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Iris Smit ◽

Dora Szabo ◽

Enikő Kubinyi

Keyword(s):

Emotional Processing ◽

Positive Emotions ◽

Attention And Memory ◽

Positivity Effect ◽

Behavioural Responses ◽

Fundamental Frequencies ◽

Age Related ◽

Significant Difference ◽

The Brain ◽

Age Related Changes

AbstractAge-related changes in the brain can alter how emotions are processed. In humans, valence specific changes in attention and memory were reported with increasing age, i.e. older people are less attentive toward and experience fewer negative emotions, while processing of positive emotions remains intact. Little is yet known about this “positivity effect” in non-human animals. We tested young (n = 21, 1–5 years) and old (n = 19, >10 years) family dogs with positive (laugh), negative (cry), and neutral (hiccup, cough) human vocalisations and investigated age-related differences in their behavioural reactions. Only dogs with intact hearing were analysed and the selected sound samples were balanced regarding mean and fundamental frequencies between valence categories. Compared to young dogs, old individuals reacted slower only to the negative sounds and there was no significant difference in the duration of the reactions between groups. The selective response of the aged dogs to the sound stimuli suggests that the results cannot be explained by general cognitive and/or perceptual decline. and supports the presence of an age-related positivity effect in dogs, too. Similarities in emotional processing between humans and dogs may imply analogous changes in subcortical emotional processing in the canine brain during ageing.

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