MiR-204 promotes apoptosis in oxidative stress-induced rat Schwann cells by suppressing neuritin expression.

Neuritin (Nrn1) is a neurotrophin that plays an important role in nervous system plasticity and repair following nerve injury. MicroRNAs (miRNAs) are a type of small non-coding RNA that regulate nearly all aspects of nerve development and survival, including apoptosis. Here it was found that miR-204 negatively regulates Nrn1 protein expression through direct interaction with Nrn1 transcript. Moreover, miR-204 activates cleaved caspase-3, enhancing the sensitivity of RSC96 Schwann cells to H2O2-induced oxidative stress and apoptosis. Thus, miR-204 expressed at a low level may create a microenvironment suitable for the repair of injured nerves by relieving the inhibition of Nrn1 transcription and stimulating the anti-apoptotic function of Schwann cells. These results provide novel insights into the roles of miR-204 in nerve injury and repair.