It is known that mitochondria, the organelles responsible for energy production within cells, lose their activity due to various factors such as aging, stress, and lack of physical activity. Director Yasutaka Ikeda of the Advanced Science Research Institute at Otsuka Pharmaceutical Co., Ltd., and his colleagues have become the first in the world to confirm that "kaempferol," a plant-derived compound, acts on mitochondria and improves the efficiency of energy production. Five human trials have further shown that kaempferol intake leads to improvements in sleep quality and athletic performance.
The interior of cells is always in a state of low oxygen, which drops to one-tenth of resting levels during physical exertion. Age also makes a significant difference: the intracellular oxygen concentration of a 60-year-old at sea level (0 m altitude) is comparable to that of a 20-year-old at 3,500 m altitude. This cellular hypoxia reduces ATP production in the mitochondria. Ikeda explained: "Oxygen, along with water and nutrition, is indispensable for energy production, the foundation of all life activity. We began this research more than ten years ago, believing that improving the body's ability to make use of oxygen would be beneficial to health."
The research group took note of the fact that people living at high altitudes maintain high athletic performance even in low-oxygen environments. They collected 341 types of high-altitude foods from around the world and identified kaempferol, found in horseradish leaves, as the compound that most effectively activates mitochondria in experiments using skeletal muscle cells. However, because naturally occurring kaempferol exists in glycoside form, only a limited number of people can break it down in the gut. To address this, the team produced OPC kaempferol by cleaving the sugar from the molecule.
A randomized trial was conducted in Tomi City, Nagano Prefecture, in which 17 men and 17 women each consumed either 50 mg of kaempferol or a placebo food once daily after breakfast. Physical activity levels, heart rate, and sleep quality were measured using wearable devices. The results showed that the kaempferol group experienced improvements in sleep duration and sleep scores, reductions in heart rate during exercise of varying intensities (from low to high), and an increase in overall physical activity. Various other experiments have also been conducted, resulting in nine published papers in journals including Sport Sciences for Health, Journal of Functional Foods, Physiological Reports, and The Journal of Nutritional Biochemistry.
In collaboration with Director Afshin Beheshti of the Center for Space Biomedicine at the University of Pittsburgh, the team has also conducted preliminary experiments to examine whether kaempferol is effective as a countermeasure against the adverse effects of spaceflight. Beheshti stated: "It is becoming clear that when three-dimensional human cell tissue models (liver, brain, heart, and microvasculature) are exposed to space radiation, the addition of kaempferol can suppress the resulting damage." A paper on these findings is scheduled for future publication.
Journal Information
Publication: Sport Sciences for Health
Title: Kaempferol enhances oxygen utilization efficiency during maximal incremental and constant-load exercises in healthy men: a randomized trial
DOI: 10.1007/s11332-024-01289-3
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