NDPIH, derived from Hericium erinaceus (monkey head mushroom), exhibits significant neurotrophic activity. It enhances extensive axonal growth and synaptic branching in cultured hippocampal neurons under serum-free conditions. Although pharmacological inhibition of actin receptor kinase B (TrkB) partially blocks the activity induced by NDPIH, the compound can independently activate the ERK1/2 signaling pathway, bypassing TrkB.