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Published on: April 28, 2023
The interrelationship among exercise intensity, endothelial function, and ghrelin in healthy humans
Kara C Anderson1,2, Emily E Grammer1, Benjamin Stephenson1
1Department of Kinesiology, School of Education and Human Development, University of Virginia, Charlottesville, Virginia, USA.
High-intensity exercise significantly improves endothelial function and suppresses ghrelin levels in both acylated and deacylated forms. These effects, particularly ghrelin suppression in females, show a moderate relationship with endothelial function improvements.
Area of Science:
- Exercise Physiology
- Endocrinology
- Cardiovascular Health
Background:
- Ghrelin, existing as acylated (AG) and deacylated (DAG) isoforms, may influence endothelial function (EF).
- Acute exercise impacts ghrelin and EF, but the role of exercise intensity remains under-explored.
Purpose of the Study:
- To investigate the distinct effects of exercise intensity and sex on endothelial function and ghrelin levels.
- To determine if exercise-induced changes in ghrelin isoforms correlate with endothelial function.
Main Methods:
- A maximal cycle ergometer test determined exercise intensities: moderate (MOD) at lactate threshold (LT) and high (HIGH) at 75% of LT to VO2peak difference.
- Participants (9 males, 8 females) underwent three conditions: CON (control), MOD, and HIGH exercise.
- Endothelial function (flow-mediated dilation, FMD) and ghrelin levels (AG, DAG) were measured pre- and post-exercise.
Main Results:
- Both MOD and HIGH exercise intensities significantly increased FMD.
- HIGH intensity exercise suppressed both AG and DAG ghrelin isoforms.
- Females showed significantly reduced DAG levels post-HIGH compared to MOD and CON, with correlations between FMD and ghrelin levels.
Conclusions:
- High-intensity exercise is crucial for suppressing ghrelin isoforms and enhancing endothelial function.
- The relationship between ghrelin suppression and endothelial function improvements appears weak to moderate, with sex-specific responses observed in DAG ghrelin.
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