Author ORCID Identifier
S. Y. Park - https://orcid.org/0000-0001-8576-7531
S. H. Park – https://orcid.org/0000-0002-1423-0929
Document Type
Article
Publication Date
3-16-2020
Publication Title
American Journal of Physiology Regulatory, Integrative and Comparative physiology
Volume
318
Issue
4
First Page
R710
Last Page
R711
Abstract
Recognizing the age-related decline in skeletal muscle feed artery (SMFA) vasodilatory function, this study examined the link between vasodilatory and mitochondrial respiratory function in the human vasculature. Twenty-four SMFAs were harvested from young (35 ± 6 yr, n = 9) and old (71 ± 9 yr, n = 15) subjects. Vasodilation in SMFAs was assessed, by pressure myography, in response to flow-induced shear stress, acetylcholine (ACh), and sodium nitroprusside (SNP) while mitochondrial respiration was measured, by respirometry, in permeabilized SMFAs. Endothelium-dependent vasodilation was significantly attenuated in the old, induced by both flow (young: 92 ± 3, old: 45 ± 4%) and ACh (young: 92 ± 3, old: 54 ± 5%), with no significant difference in endothelium-independent vasodilation. Complex I and I + II state 3 respiration was significantly lower in the old (CI young: 10.1 ± 0.8, old: 7.0 ± 0.4 pmol·s−1·mg−1; CI + II young: 12.3 ± 0.6, old: 7.6 ± 0.4 pmol·s−1·mg−1). The respiratory control ratio (RCR) was also significantly attenuated in the old (young: 2.2 ± 0.1, old: 1.1 ± 0.1). Furthermore, state 3 (CI + II) and 4 respiration, as well as RCR, were significantly correlated (r = 0.49–0.86) with endothelium-dependent, but not endothelium-independent, function. Finally, the direct intervention with mitochondrial-targeted antioxidant (MitoQ) significantly improved endothelium-dependent vasodilation in the old but not in the young. Thus, the age-related decline in vasodilatory function is linked to attenuated vascular mitochondrial respiratory function, likely by augmented free radicals.
Recommended Citation
Vasodilatory and vascular mitochondrial respiratory function with advancing age: evidence of a free radically mediated link in the human vasculature Soung Hun Park, Oh Sung Kwon, Song-Young Park, Joshua C. Weavil, Jay R. Hydren, Van Reese, Robert H. I. Andtbacka, John R. Hyngstrom, and Russell S. Richardson American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 2020 318:4, R701-R711
Comments
This is the accepted manuscript of an article published in the American Journal of Physiology-Regulatory, Integrative and Comparative Physiology on March 16, 2020 and can be accessed at https://doi.org/10.1152/ajpregu.00268.2019