The gut metabolite indole-3 propionate promotes nerve regeneration and repair
I searched for some foods to increase Indole-3 Proprionate and this page is pretty good.  [1] It tells what to eat (fermented foods, fiber, sprouted seeds) and what to avoid (sugar, simple starches, omega-6-heavy oils).  It also introduced me to fermented bean curd.  Can't want to try it.[1] https://go.ixcela.com/metabolite-library/ipa