Exercise in a Pill

Leiter, O., Brici, D., Fletcher, S. J., Yong, X. L. H., Widagdo, J., Matigian, N., Schroer, A. B., Bieri, G., Blackmore, D. G., Bartlett, P. F., Anggono, V., Villeda, S. A., & Walker, T. L. (2023). Platelet-derived exerkine CXCL4/platelet factor 4 rejuvenates hippocampal neurogenesis and restores cognitive function in aged mice. Nature communications, 14(1), 4375. https://doi.org/10.1038/s41467-023-39873-9

Physical exercise has long been championed for the benefits it provides. For example, studies have proven that exercise is capable of strengthening muscle tissue and building endurance. In addition to those two well known benefits, there are a variety of others that have also been demonstrated. Exercise can improve the immune system’s ability to fend off diseases, decrease the risk of depression, and increase attention span. Most importantly, exercise has demonstrated that it can improve brain health. A study noted that physical activity regulated epigenetic changes, or the gene alterations that occur as a result of environmental changes. This is beneficial as it protects developmental factors from stimuli such as stress, diet, and toxin exposure. Another noted benefit is synaptic plasticity, the ability of the connections between neural cells to change over time, due to its role in learning and memory.

In addition to basic brain advantages, there is evidence of exercise’s role in protection against the prognosis of brain disorders such as Alzheimer’s disease, which causes memory impairment. Specifically in elderly patients, the rates of cognitive decline are halted or slowed when they participate in physical exercise; this also helps with preventing a loss of muscle control, a key symptom of ALS (amyotrophic lateral sclerosis). However, there are a variety of factors that limit the elderly from performing physical exercise such as mobility limitations or critical health conditions. Thus, it is imperative that the discovery of a novel tool or substance with the same effects as exercise is created to benefit the elderly.

A previous paper found that exerkines, signaling compounds that are released into the bloodstream during exercise, may play a major role in the memory improvements triggered by physical activity. From this study, a group of researchers endeavored to discover a compound that can serve as an “exercise pill.” They discovered that platelets, immune cells that help form blood clots to prevent bleeding, are activated during exercise and can release a specific exerkine they termed as PF4 (platelet factor 4). Using mice, the scientists performed a series of experiments to test the effects of PF4 in memory and the formation of neurons. They saw that PF4 could increase the creation rate of neurons in the hippocampus, the brain region responsible for both learning and memory. This would enhance the brain’s ability to adapt to new environments and respond to new stimuli. In another one of their procedures, they saw that PF4 rejuvenated cognitive function in aged mice, leading to massive improvements in brain activity and processing.

The results from their study proved that PF4 can promote cognitive function, improve memory, and cause neuron formation within the memory-centered hippocampus. Although the experiments were conducted in mice, it is likely that similar results will be observed in humans. The researchers hope to progress their study to a human trial and create pills containing PF4.

Works Cited:

Centers for Disease Control and Prevention. (2023a, July 12). Health benefits of physical activity for children, adults, and adults 65 and older. Centers for Disease Control and Prevention. https://www.cdc.gov/physicalactivity/basics/adults/health-benefits-of-physical-activity.html

Centers for Disease Control and Prevention. (2023b, August 1). Benefits of physical activity. Centers for Disease Control and Prevention. https://www.cdc.gov/physicalactivity/basics/pa-health/index.htm#:~:text=Being%20physically%20active%20can%20improve,activity%20gain%20some%20health%20benefits.

Centers for Disease Control and Prevention. (2022, August 15). What is epigenetics?. Centers for Disease Control and Prevention. https://www.cdc.gov/genomics/disease/epigenetics.htm

Liang, J., Wang, H., Zeng, Y., Qu, Y., Liu, Q., Zhao, F., Duan, J., Jiang, Y., Li, S., Ying, J., Li, J., & Mu, D. (2021). Physical exercise promotes brain remodeling by regulating epigenetics, neuroplasticity and neurotrophins. Reviews in the neurosciences, 32(6), 615–629. https://doi.org/10.1515/revneuro-2020-0099