Ghrelin promotes midbrain neural stem cells differentiation to dopaminergic neurons through Wnt/β-catenin pathway

Ghrelin plays a neuroprotective role in the process of dopaminergic (DAergic) neurons degeneration in Parkinson's disease (PD). However, it still largely unknown whether ghrelin could affect the midbrain neural stem cells (mbNSCs) from which DAergic neurons are originated. In the present study, we observed that ghrelin enhanced mbNSCs proliferation, and promoted neuronal differentiation especially DAergic neuron differentiation both in vitro and ex vivo. The messenger RNA levels of Wnt1, Wnt3a, and glial cell line-derived neurotrophic factor were increased in response to the ghrelin treatment. Results showed that Wnt/β-catenin pathway was relevant to this DAergic neuron differentiation induced by ghrelin. Our finding gave a new evidence that ghrelin may enable clinical therapies for PD by its neurogenesis role.