PKC signaling pathway is modulated by lanthanum in RAW264.7 macrophages
Bacterial products trigger inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) production in inflammatory and tissue cells. In inflammation, NO acts as an important mediator having both proinflammatory and destructive effects. Previously, we have reported that the exposure of RAW264.7 cells to lanthanum chloride results in reduced lipopolysaccharide (LPS)-induced NO production and iNOS gene expression. Protein kinase C (PKC) is a family of serine-threonine protein kinase isoenzymes involved in signal transduction pathways related to inflammatory responses. Our aim in the present study was to assess the role of PKC in the regulation of lanthanum on iNOS expression in murine RAW264.7 macrophages and the mechanisms involved. RAW 264.7 murine macrophage cells were pretreated with media containing lanthanum chloride (LaCl3) or not, then activated by LPS. In parallel cultures，normal control and LaCl3 control were set. Then the cells were immunofluorescent stained or lysised, separated by electrophoresis, and probed for PKCα and phosphorylated PKCα (pPKCα). The levels of iNOS protein expression in the RAW264.7 cells were measured as a possible mechanism of lanthanum-induced PKC modulation. LPS caused the translocation and phosphorylation of PKCα as well as increased the iNOS expression, which were markedly attenuated by LaCl3 pretreatment. All the results suggest that LaCl3 alters activation and translocation of PKCα. Furthermore, even lanthanum does not alter the PKCα signaling pathway by itself; it represses the activation of the signaling by LPS, suggesting that the biological effects of the metal ion on macrophage function may only be manifest upon activation.
lanthanum lipopolysaccharides PKC iNOS
Fei Guo Yuan-Lei Lou Yang Wang An Xie Guo-Hui Li
Burns Institute of the First Affiliated Hospital of Nanchang University, Nanchang, China, 330006; po Institute of Urology, the First Affiliated Hospital of Nanchang University, Nanchang, China, 330006 Burns Institute of the First Affiliated Hospital of Nanchang University, Nanchang, China, 330006
国际会议
The 5th International Forum on Post-genome Technologies(5IFPT)(第五届国际后基因组生命科学技术学术论坛)
苏州
英文
2007-09-10（万方平台首次上网日期，不代表论文的发表时间）