Platelet factor 4 (PF4), a protein involved in wound healing, has been found to potentially have anti-ageing effects and improve learning and memory in ageing mice. This has led researchers to explore whether PF4 could be used to treat age-related cognitive disorders like Alzheimer’s disease. Injecting PF4 into aged mice resulted in shifts in immune cell ratios, decreases in damaging inflammation in the hippocampus, and increases in molecules that promote synaptic plasticity. Cognitive tests also showed that aged mice injected with PF4 performed better than aged control mice. Other studies also suggest that PF4 plays a role in regulating aspects of ageing such as synaptic plasticity and neuron formation.
https://www.nature.com/articles/d41586-023-02563-z