Succinate Dehydrogenase (SDH)-subunit C Regulates Muscle Oxygen Consumption and Fatigability in an Animal Model of Pulmonary Emphysema

AbstractPatients with pulmonary emphysema often develop locomotor muscle dysfunction, which is independently associated with disability and higher mortality in that population. Muscle dysfunction entails reduced force-generation capacity which partially depends on fibers’ oxidative potential, yet very little mechanistic research has focused on muscle respiration in pulmonary emphysema. Using a recently established animal model of pulmonary emphysema-driven skeletal muscle dysfunction, we found downregulation of succinate dehydrogenase (SDH) subunit C in association with lower oxygen consumption and fatigue-tolerance in locomotor muscles. Reduced SDH activity has been previously observed in muscles from patients with pulmonary emphysema and we found that SDHC is required to support respiration in cultured muscle cells. Moreover, in-vivo gain of SDH function in emphysema animals muscles resulted in better oxygen consumption rate (OCR) and fatigue tolerance. These changes correlated with a larger number of relatively more oxidative type 2-A and 2X fibers, and a reduced amount of 2B fibers. Our data suggests that SDHC is a key regulator of respiration and fatigability in pulmonary emphysema-driven skeletal muscles, which could be impactful to develop strategies aimed at attenuating this comorbidity.

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Fatigue Increases in Resting Muscle Oxygen Consumption after a Women’s Soccer Match

International Journal of Sports Medicine ◽

10.1055/a-1177-0849 ◽

2020 ◽

Author(s):

Aldo Alfonso Vasquez Bonilla ◽

Rafael Timon ◽

Alba Camacho-Cardeñosa ◽

Marta Camacho-cardeñosa ◽

Samantha Guerrero ◽

...

Keyword(s):

Oxygen Consumption ◽

Muscle Pain ◽

Perceived Exertion ◽

Arterial Occlusion ◽

Muscle Oxygenation ◽

Soccer Match ◽

Muscle Oxygen ◽

Muscle Oxygen Consumption ◽

Resting Muscle ◽

Women's Soccer

AbstractCurrently, near infrared spectroscopy has a clear potential to explain the mechanisms of fatigue by assessing muscle oxygenation. The objective of the study was to observe the changes in muscle oxygen consumption after an official women’s soccer match. The sample was 14 players who competing in the second division of Spain of women’s soccer. They were evaluated before, immediately after and 24 h after the official match. Biochemical parameters were measured in blood plasma (BUN, GOT, LDH, CPK). The jumping in countermovement, perceived exertion and perceived muscle pain were also assessed. The muscle oxygen consumption and muscle oxygen saturation were evaluated in the gastrocnemius muscle with an arterial occlusion test. ANOVA of repeated measures, Pearson’s correlation and Hopkins’ statistics were applied to measure the magnitudes of change and effect size. There was observed an increase in kinetics of SmO2 at 24 h after the official match, using arterial occlusion. In addition, it was found that the increase in muscle oxygenation correlated with fatigue indicators, such as the increases in LDH, perceived muscle pain and the decrease in countermovement. It is confirmed that a women’s soccer match produced an increase of resting muscle oxygenation in 24 h after the official match.

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