earticle

영어

Glycosphingolipids including gangliosides play important regulatory roles in cell prolifera-tion and differentiation. UDP-glucose:ceramide glucosyltransferase(Ugcg) catalyze the initial step in glycosphingolipids biosynthesis pathway. In this study, Ugcg expression was reduced to approximately 80% by short hairpin RNAs(shRNAs) to evaluate the roles of glycosphingolipids in proliferation and gangliosdies differentiation of PK15. HPTLC/immunofluorescence analyses of shRNA transfected PK15 revealed that treatment with Ugcg-shRNA decreased expression of major gangliosides, GM1 and GD1b. Furthermore, MTT and western blot/immunofluorescence analyses demonstreated that inhibition of the Ugcg expression in PK15 resulted in decrease of cell proliferation. In addition to we showed that inflammatory respon-ses in PK15 and gangliosides knock-down PK15 cells stimulated with Escherichia coli lipopolysaccharide(LPS). The gangliosides GM3, GM2, GD3, GD1a and GD1b were detected in normal PK15 cell. However almost gangliosides undetected in gangliosides knock-down PK15 cell. In addition we found that the expression levels of TNF-α, indu-cible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and we measured the production of NO. The expression of inflammatory proteins, TNF- α, iNOS and COX-2 the elevated concentration in gangliosides knock-down PK15 cell. These results suggest that gangliosides interact with components of the proinflammatory response pathway and might, therefore, be relevant for designing future therapeutic strategies intended to prolong xenograft survival.