Deletion of CD73 increases exercise power in mice

Area of Science:

• Exercise Physiology
• Biochemistry
• Molecular Biology

Background:

• Ecto-5'-nucleotidase (CD73) generates extracellular adenosine, activating adenosine A2A receptors.
• Adenosine A2A receptors are implicated in the ergogenic (performance-enhancing) effects of caffeine.
• The specific role of CD73 in regulating exercise performance remains to be fully elucidated.

Purpose of the Study:

• To investigate the role of CD73 in exercise performance.
• To compare the physical performance of wild-type (WT) and CD73 knockout (KO) female mice.
• To assess running power, oxygen uptake (V̇O2), and respiratory exchange ratio (RER) as key indicators of exercise capacity.

Main Methods:

• A treadmill-graded exercise test was employed to evaluate maximal physical performance.
• Measurements included spontaneous locomotion, submaximal and maximal running power, oxygen uptake (V̇O2max), and respiratory exchange ratio (RER).
• Comparisons were made between female WT and CD73-KO mice.

Main Results:

• Spontaneous locomotion and submaximal exercise parameters were similar between CD73-KO and WT mice.
• Maximal oxygen uptake (V̇O2max) indicated equivalent aerobic power between groups.
• CD73-KO mice exhibited significantly higher critical power (43.7% increase) and a modest increase in maximum RER (3.8%).

Conclusions:

• The absence of CD73 (KO) demonstrated an ergogenic effect, enhancing physical performance.
• CD73 deficiency leads to improved exercise capacity, particularly in terms of critical power and maximal RER.
• These findings suggest CD73 plays a regulatory role in modulating exercise performance.