This is a competitive renewal proposal for R01 AG13038, currently in its 8'"""""""" consecutive year of funding. The focus of this award has been to study the effects of aging and lifestyle interventions on large artery function and structure. In the present plan we propose to continue our productive work on this theme by testing the following tightly focused set of working hypotheses: 1) regular moderate-intensity aerobic exercise (daily brisk walking) increases peripheral conduit artery flow-mediated dilation (FMD), a measure of endothelium-dependent vasodilatory capacity and overall arterial vascular health, in previously sedentary middle-aged and older adults;2) an increase in nitric oxide (NO) bioavailability is the key mechanism by which regular aerobic exercise improves FMD;3) an increase in the bioavailability of the critical co-factor for NO synthesis, tetrahydrobiopterin (BH4), is one mechanism by which regular aerobic exercise increases NO bioavailability and FMD;4) a reduction in vascular oxidative stress, related in part to an increase in extracellular superoxide dismutase (ecSOD), is an important mechanism by which regular aerobic exercise increases BH4 and NO bioavailability and FMD;5) changes in the expression of proteins encoded by specific genes in arterial endothelial cells (i.e., increases in enzymatic antioxidant, eNOS, and phosphorylated eNOS protein expressions, and reductions in oxidant enzyme, endothelin-1, and angiotensin II receptor protein expressions) are among the key molecular mechanisms associated with the favorable effects of regular aerobic exercise on oxidative stress, BH4 and NO bioavailability, and FMD. To test these hypotheses we will conduct 2 complementary randomized aerobic exercise intervention trials in sedentary healthy middle-aged and older (age 55-75 years) men and women. The mechanistic roles played by changes in vascular oxidative stress and BH4 and NO bioavailability in mediating improvements in FMD will be determined in experimental sessions conducted before and after a 12-week exercise (or non-exercise attention control) condition. Insight into the molecular mechanisms involved will be obtained using a novel translational physiology research technique by which changes in arterial endothelial cell protein expression of genes involved in the regulation of these cellular and systemic adaptations to habitual exercise will be determined via quantitative immunofluorescence. The expected results will provide new, clinically important insight into the efficacy of moderate aerobic exercise for restoring arterial endothelial function in middle-aged and older sedentary adults, and the underlying mechanisms. In particular, the proposed research will provide the first information on 2 highly novel mechanisms by which regular exercise may augment NO bioavailability: 1) by increasing BH4 bioavailability;and 2) by producing changes in the expression of key arterial endothelial cell proteins involved in determining endothelial function. :_OVIDED. University of Colorado-Boulder, Boulder, Colorado

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Method to Extend Research in Time (MERIT) Award (R37)
Project #
5R37AG013038-17
Application #
8290363
Study Section
Special Emphasis Panel (NSS)
Program Officer
Dutta, Chhanda
Project Start
1998-02-01
Project End
2014-06-30
Budget Start
2012-07-15
Budget End
2013-06-30
Support Year
17
Fiscal Year
2012
Total Cost
$286,917
Indirect Cost
$97,533
Name
University of Colorado at Boulder
Department
Physiology
Type
Schools of Arts and Sciences
DUNS #
007431505
City
Boulder
State
CO
Country
United States
Zip Code
80309
Pierce, G L; Harris, S A; Seals, D R et al. (2016) Estimated aortic stiffness is independently associated with cardiac baroreflex sensitivity in humans: role of ageing and habitual endurance exercise. J Hum Hypertens 30:513-20
Su, Zhen; Hu, Li; Cheng, Jinzhong et al. (2016) Acupuncture plus low-frequency electrical stimulation (Acu-LFES) attenuates denervation-induced muscle atrophy. J Appl Physiol (1985) 120:426-36
Seals, Douglas R; Justice, Jamie N; LaRocca, Thomas J (2016) Physiological geroscience: targeting function to increase healthspan and achieve optimal longevity. J Physiol 594:2001-24
DeVan, Allison E; Johnson, Lawrence C; Brooks, Forrest A et al. (2016) Effects of sodium nitrite supplementation on vascular function and related small metabolite signatures in middle-aged and older adults. J Appl Physiol (1985) 120:416-25
Kaplon, Rachelle E; Hill, Sierra D; Bispham, Nina Z et al. (2016) Oral trehalose supplementation improves resistance artery endothelial function in healthy middle-aged and older adults. Aging (Albany NY) 8:1167-83
Martens, Christopher R; Seals, Douglas R (2016) Practical alternatives to chronic caloric restriction for optimizing vascular function with ageing. J Physiol 594:7177-7195
Jablonski, Kristen L; Klawitter, Jelena; Chonchol, Michel et al. (2015) Effect of dietary sodium restriction on human urinary metabolomic profiles. Clin J Am Soc Nephrol 10:1227-34
Justice, Jamie N; Gioscia-Ryan, Rachel A; Johnson, Lawrence C et al. (2015) Sodium nitrite supplementation improves motor function and skeletal muscle inflammatory profile in old male mice. J Appl Physiol (1985) 118:163-9
Justice, Jamie N; Johnson, Lawrence C; DeVan, Allison E et al. (2015) Improved motor and cognitive performance with sodium nitrite supplementation is related to small metabolite signatures: a pilot trial in middle-aged and older adults. Aging (Albany NY) 7:1004-21
Jablonski, Kristen L; Donato, Anthony J; Fleenor, Bradley S et al. (2015) Reduced large elastic artery stiffness with regular aerobic exercise in middle-aged and older adults: potential role of suppressed nuclear factor κ B signalling. J Hypertens 33:2477-82

Showing the most recent 10 out of 141 publications