A recent study published in the journal Nature Communications has revealed that injecting molecules derived from blood can mimic the cognitive benefits of exercise in the brains of mice. This breakthrough discovery has the potential to lead to new treatments aimed at improving cognition in patients with Alzheimer’s disease.
The research focused on platelets, the small cells responsible for blood clotting. Scientists found that platelets secrete a protein that rejuvenates nerve cells in aged mice, similar to the effects of physical exercise on the brain.
“Although we knew that exercise increases the production of new neurons in the hippocampus, the mechanism behind this was unclear,” explains study co-author Odette Leiter from the University of Queensland in Australia. “Our previous research indicated a role for platelets, but this study demonstrates that platelets are actually necessary for this effect in aged mice.”
The study specifically examined exerkines, biological compounds released into the bloodstream during exercise that are believed to stimulate a response in the brain. The researchers identified a molecule called CXCL4/Platelet factor 4 (PF4) released from platelets after exercise, which results in regenerative and cognitive improvements when injected into aged mice.
According to the study, “We demonstrate that platelets are activated by exercise and are essential for the exercise-induced increase in hippocampal precursor cell proliferation in aged mice.”
The implications of these findings are significant for the development of drug interventions targeting age-related cognitive decline, such as in Alzheimer’s disease. “Exercise may not be possible for many individuals with health conditions, mobility issues, or advanced age, making pharmacological intervention an important area of research,” says Tara Walker, another author of the study. “By targeting platelets, we can promote neurogenesis, enhance cognition, and counteract age-related cognitive decline.”
The next step for scientists is to test the response in mice with Alzheimer’s disease before progressing to human trials. However, it is important to note that any therapeutic treatments developed based on this study should not be viewed as a substitute for exercise.
“While it could potentially help elderly individuals, as well as those who have experienced brain injuries or strokes, improve cognition,” warns Dr. Walker, “exercise remains an essential component of maintaining brain health.”
The researchers conclude, “Together, these findings emphasize the role of platelets in mediating the rejuvenating effects of exercise during the natural aging process of the brain.”