Effect of olfactory ensheathing cells combined with chitosan on inhibition of P2×4 receptor over-expression-mediated neuropathic pain

Abstract

Neuropathic pain (NPP) is a clinically refractory disease that causes pain to patients, and its treatment has always been an urgent problem to be solved. P2X4 receptor (P2X4R) plays a key role in the pathogenesis of neuropathic pain. Therefore, the aim of this studies to explore the effect of olfactory ensheathing cells combined with chitosan (OECs+CS) transplantation on NPP caused by sciatic nerve injury in rats, and its relationship with the expression levels of P2X4R in the L4-5 dorsal root ganglion (DRG). In this study, olfactory ensheathing cells (OECs) were cultured, chitosan (CS) was prepared, and the compatibility of CS and OECs was detected by MTT method. Animal model of chronic constrictive sciatic nerve injury (CCI) was made, OECs and OECs+CS were transplanted to the region surrounding the chronic sciatic nerve injury, and the difference between the two groups in the treatment of NPP was compared. The mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were measured by using behavioral method. in situ hybridization and Western-blotting were used to detect the expression of P2X4R mRNA and protein in the DRG. These results showed that OECs had good biocompatibility with CS. Compared with the CCI, the MWT and TWL were significantly increased (P＜0.05), the expression levels of P2X4R mRNA and protein in the OECs and OECs+CS group were significantly reduced (P＜0.05). Compared with the OECs, the expression levels of P2X4R mRNA and protein in the OECs+CS group were significantly reduced (P＜0.05), the MWT and TWL were significantly increased (P＜0.05). We conclude that OECs+CS can better inhibit P2X4R over-expression-mediated NPP, and its therapeutic effect was superior to simple OECs transplantation, which may become another potential method for the treatment of NPP.