Author ORCID Identifier
Park - https://orcid.org/0000-0001-8576-7531
Anderson - https://orcid.org/0000-0003-2341-4962
Mishra - https://orcid.org/0000-0002-7810-9239
Schieber - https://orcid.org/0000-0002-1913-8582
Document Type
Article
Publication Date
4-14-2022
Publication Title
American Journal of Physiology Heart and Circulatory Physiology
Volume
322
Issue
5
First Page
H867
Last Page
H879
Abstract
Peripheral artery disease (PAD) is an atherosclerotic disease that impairs blood flow and muscle function in the lower limbs. A skeletal muscle myopathy characterized by mitochondrial dysfunction and oxidative damage is present in PAD; however, the underlying mechanisms are not well established. We investigated the impact of chronic ischemia on skeletal muscle microcirculatory function and its association with leg skeletal muscle mitochondrial function and oxygen delivery and utilization capacity in PAD. Gastrocnemius samples and arterioles were harvested from patients with PAD (n = 10) and age-matched controls (Con, n = 11). Endothelium-dependent and independent vasodilation was assessed in response to flow (30 μL·min−1), acetylcholine, and sodium nitroprusside (SNP). Skeletal muscle mitochondrial respiration was quantified by high-resolution respirometry, microvascular oxygen delivery, and utilization capacity (tissue oxygenation index, TOI) were assessed by near-infrared spectroscopy. Vasodilation was attenuated in PAD (P < 0.05) in response to acetylcholine (Con: 71.1 ± 11.1%, PAD: 45.7 ± 18.1%) and flow (Con: 46.6 ± 20.1%, PAD: 29.3 ± 10.5%) but not SNP (P = 0.30). Complex I + II state 3 respiration (P < 0.01) and TOI recovery rate were impaired in PAD (P < 0.05). Both flow and acetylcholine-mediated vasodilation were positively associated with complex I + II state 3 respiration (r = 0.5 and r = 0.5, respectively, P < 0.05). Flow-mediated vasodilation and complex I + II state 3 respiration were positively associated with TOI recovery rate (r = 0.8 and r = 0.7, respectively, P < 0.05). These findings suggest that chronic ischemia attenuates skeletal muscle arteriole endothelial function, which may be a key mediator for mitochondrial and microcirculatory dysfunction in the PAD leg skeletal muscle. Targeting microvascular dysfunction may be an effective strategy to prevent and/or reverse disease progression in PAD.
Recommended Citation
Impaired microcirculatory function, mitochondrial respiration, and oxygen utilization in skeletal muscle of claudicating patients with peripheral artery disease Song-Young Park, Elizabeth J. Pekas, Cody P. Anderson, Tyler N. Kambis, Paras K. Mishra, Molly N. Schieber, TeSean K. Wooden, Jonathan R. Thompson, Kyung Soo Kim, and Iraklis I. Pipinos American Journal of Physiology-Heart and Circulatory Physiology 2022 322:5, H867-H879
Comments
This is the accepted manuscript for an article published in American Journal of Physiology Heart and Circulatory Physiology on April 14, 2022 and can be accessed at https://doi.org/10.1152/ajpheart.00690.2021