New research suggests that the blood protein GDF11 could promote youthfulness in the brain, heart and skeletal muscles. Two new papers released from the Harvard Stem Cell Institute have shown that old mice treated with GDF11 isolated from the blood of younger mice displayed improved cognitive function and running endurance.
Previous work conducted at Stanford University had shown that blood plasma transfusions from younger to older mice had striking regenerative effects. The Harvard group sought to build on these findings by identifying the protein responsible for these changes. This was achieved via a two-pronged approach; treating old mice with young mouse blood via a surgical graft, and injecting purified GDF11 proteins into old recipients.
Treated mice were able to run longer than control mice, and characteristic changes associated with ageing (such as heart enlargement) were reduced. Young mice and treated mice avoid the smell of mint where old mice do not, due to a heightened sense of smell. 3D imaging of the brain showed the olfactory region had increased blood flow, as did the rest of the brain.
How does GDF11 work? It appears that the injected mice had increased vascularisation, and in turn increased blood flow. This may facilitate neurogenesis in the brain, improving cognitive ability. In muscle tissues, the ageing-associated DNA damage was repaired in the muscle stem cells. Even mitochondria – our intracellular power plants – respond to GDF11, becoming more healthy and youthful.
The most exciting aspect of GDF11 transfer is its widespread effects, notably in the brain and heart. Scientists have already highlighted its possible clinical uses, notably in the context of neurodegenerative disorders such as Alzheimer’s disease, and clinical trials are forecast to take place within 3-5 years.