The altered levels of sulfatide are observed in various kinds of diseases in the nervous system. In our previous reports, sulfatide synthase gene expression in the spinal cord was increased one day after intraplantar injection of complete Freund’s adjuvant (CFA). On the other hand, intrathecal injection of sulfatide led to mechanical allodynia. Sulfatide is not only the major glycosphingolipid in the myelin sheath but also the potent selectin activator. Thus, we investigated the effect of a selectin inhibitor, bimosiamose, on the sulfatide-induced mechanical allodynia.
Intrathecal sulfatide injection produced an increase in mRNA expression of inflammatory cytokines such as TNF-α and interleukin-1β in the spinal cord. Bimosiamose inhibited the increase of these cytokine gene expressions and the mechanical allodynia produced by sulfatide, suggesting that sulfatide induced inflammatory cytokine expression via selectin activation. Furthermore, bimosiamose also attenuated the CFA-induced mechanical allodynia and lipid analysis using thin-layer chromatography revealed the sulfatide accumulation in the spinal cord during inflammatory pain.
These results indicated that the accumulated sulfatide in the spinal cord enhanced selectin activation during inflammatory pain, which resulted in mechanical allodynia.