Repair Effects of Bone Marrow Mesenchymal Stem Cells on Demyelination of Trigeminal Ganglion in Rats with Trigeminal Neuralgia

OBJECTIVE: The current study investigated the effects of bone marrow mesenchymal stem cells (BMSCs) on pain behavior in rats with trigeminal neuralgia induced by infraorbital nerve chronic constriction injury (ION-CCI), and the repair effects of BMSCs on pathological changes in trigeminal ganglion demyelination. METHODS: BMSCs or phosphate-buffered saline (PBS) alone were injected around trigeminal ganglion in ION-CCI rats via a rat brain stereotaxic apparatus. Mechanical pain threshold (von Frey test) and face grooming behavior were measured in each group. Recovery of demyelination of trigeminal ganglion was observed via electron microscopy 2 weeks later, and BMSC differentiation was observed via immunofluorescence. RESULTS: Rats in the BMSC group exhibited significant improvements in mechanical pain threshold and face grooming behavior compared with the PBS group. BMSCs could repair demyelinating changes in trigeminal ganglion in ION-CCI rats. Only cells expressing GFAP, S-100, and p75 were observed via immunofluorescence, and no PKH67-labeled BMSCs were observed in the trigeminal ganglion. No BMSC differentiation was observed in the trigeminal ganglion. CONCLUSION: Injection of BMSCs around the trigeminal ganglion could relieve trigeminal neuralgia effectively and repair trigeminal ganglion demyelination. No differentiation of BMSCs injected around the trigeminal ganglion into Schwann cells was observed. The mechanism of trigeminal neuralgia demyelination repair requires further investigation.