Glycosphingolipids (GSLs) play many important roles in cellular interaction, proliferation, vesicular transport and intracellular signal transduction. Our previous study revealed that the gene expressions of six glycosyltransferases in the GSLs biosynthesis pathway were altered in the spinal cord and dorsal root ganglion one day or 15 days after inflammation caused by complete Freund's adjuvant (CFA). We focused on CFA-induced upregulation of gal3st1 glycosyltransferase that catalyzes the synthesis of sulfatides, the sulfated GSLs in myelin structures, because the roles of sulfatides in nociceptive behavior are unclear. In this study, we intrathecally injected sulfatides into naïve mice and measured mechanical thresholds using von Frey test. Indeed, sulfatides induced mechanical allodynia within 40 min.
The report that sulfatides induce cytokine production from glial cells (Jeon SB et al., 2008 J. Immunology) leads to the hypothesis of the involvement of glial activation by spinal sulfatide during allodynia. Future studies are needed to reveal the molecular mechanisms of how sulfatides are involved in the pain transduction.
