论文部分内容阅读
探讨单核细胞在炎症因子刺激下通过功能蛋白O-糖基化和p38 MAPK磷酸化、调控其对血管内皮的粘附和侵袭的分子机制。将IFN-γ与LPS体外共刺激后的THP-1细胞加至单层血管内皮细胞EA.hy926共培养,观察单核细胞对血管内皮的粘附和侵袭;并通过测量电阻变化来反应血管内皮通透性的改变。采用Western blot方法检测单核细胞THP-1中p38 MAPK磷酸化的变化,O-GLcNAc糖基转移酶(OGT)和O-GLcNAc糖基化蛋白表达量的变化。分析验证p38 MAPK抑制剂对IFN-γ与LPS诱导的单核细胞对血管内皮粘附和迁移的影响,同时检测OGT、O-GLcNAc糖基化蛋白差异表达的影响。结果显示,IFN-γ与LPS可以共作用促进THP-1对血管内皮的粘附和侵袭,降低血管内皮通透性。同时激活p38 MAPK,此过程与OGT及O-GLcNAc糖基化蛋白表达降低相关。采用p38抑制剂预处理,可逆转上述IFN-γ与LPS诱导的生物学变化。综上,在炎症反应中,单核细胞对血管内皮的粘附和侵袭力的变化受功能蛋白糖基化和磷酸化的双向调控。
To investigate the molecular mechanism of monocyte-induced adhesion and invasion to vascular endothelial cells through functional O-glycosylation and p38 MAPK phosphorylation stimulated by inflammatory cytokines. THP-1 cells co-stimulated with LPS in vitro were added to monolayer endothelial cells EA.hy926 to observe the adhesion and invasion of monocytes to the vascular endothelium; and the changes of resistance were measured to reflect the changes of vascular endothelial Change in permeability. The changes of p38 MAPK phosphorylation, O-GLcNAc glycosyltransferase (OGT) and O-GLcNAc glycosylated protein expression in monocytes THP-1 were detected by Western blot. The effect of p38 MAPK inhibitor on the adhesion and migration of monocytes to vascular endothelial cells induced by IFN-γand LPS was analyzed. The differential expression of OGT and O-GLcNAc glycosylated protein was also tested. The results showed that IFN-γand LPS can promote the adhesion and invasion of THP-1 to vascular endothelium and reduce the vascular endothelial permeability. Activation of p38 MAPK at the same time, the process of OGT and O-GLcNAc glycosylation protein expression decreased. Pretreatment with p38 inhibitor reverses the biological changes induced by IFN-γ and LPS. In conclusion, changes in the adhesion and invasiveness of monocytes to vascular endothelium are regulated bidirectionally by both glycosylation and phosphorylation of functional proteins in the inflammatory response.