This is cool but I don't see neural stem cells grafting and this hydrogel have clinical applications in humans, because the brain is very difficult to access, even via the CSF (diffusion is very limited), without very invasive way like trepanation.<p>I think a more realistic clinical approach is astrocytes to neurons reprogramming using vectors like AAV9 to pass the blood brain barrier and activate genes to convert them [1] to different types based on the genes (NGN2: glutamatergic, ASCL1: GABAergic, dopaminergic, cholinergic...). This has the added benefit of reduced cancer risk (direct reprogramming) and astrocytes have a regional identity [2].<p>[1]: <a href="https://www.embopress.org/doi/full/10.15252/emmm.202114797" rel="nofollow">https://www.embopress.org/doi/full/10.15252/emmm.202114797</a>
[2]: <a href="https://www.science.org/doi/full/10.1126/sciadv.abe8978" rel="nofollow">https://www.science.org/doi/full/10.1126/sciadv.abe8978</a>
TLDR: “They used hydrogel materials, in combination with neural stem cells, to grow new brain tissue.”<p>The hydrogel for scaffolding it doesn’t promote neuronal growth on its own. Still quite promising.
What would happen if we took a pill and grew a ton of extra neurons in our digestive system? We’ve got about 100 million neurons in our gut, which is comparable to a duck. I feel like it’d probably just be weird.