Roles of Protein Kinase C on BSA-AGEs-Induced Nitric Oxide Synthase Expression in RAW 264.7 Macrophages

• Main Authors: Chien-Hsi Chang, 張鑑熹
• Other Authors: Horng-Mo Lee Ph.D.
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/95018862945444773874

碩士 === 台北醫學院 === 生物醫學技術研究所 === 89 === Abstract Title of Thesis: Roles of protein kinase C on BSA-AGEs-induced nitric oxide synthase expression in RAW 264.7 macrophages. Author: Chien-Hsi Chang Thesis advised by: Horng-Mo Lee Ph.D. We previously found that Advanced Glycosylation End Products (AGEs) induced nitric oxide synthaseⅡ (iNOS) expression in RAW 264.7 cells. The signaling pathway involved in protein kinase C activation and the roles of PKC isoforms in AGEs-induced NO production in RAW 264.7 cells were investigated. BSA-AGEs caused a dose- and time-dependent increase in NO release and inducible NO synthase (iNOS) expression, but BSA alone did not induce iNOS expression. The polymyxin B（LPS inhibitor）also did not inhibit BSA-AGEs induced iNOS expression. The tyrosine kinase inhibitor genistein attenuated BSA-AGEs-induced NO release and iNOS expression in RAW 264.7 cells. Additionally, the phosphoinositide-specific phospholipase C (PI-PLC) inhibitor, U73122, the phosphatidylcholine-specific phospholipase C (PC-PLC) inhibitor, D609, and the PKC inhibitors including staurosporine, Ro 31-8220, and Go 6976 all inhibited the BSA-AGEs-induced iNOS expression. BSA-AGEs stimulated PIP2 turnover was attenuated by PI-PLC inhibitor, U73122 and tyrosine kinase inhibitor, genistein. Western blot analysis revealed that incubation of the RAW 264.7 cells with BSA-AGEs, results in PKC-a, -b1, -d, and -h translocation, indicating the possible involvement of one or all of PKC-a, -b1, -d, and -h in AGEs-mediated effects. These data suggest that BSA-AGEs activate PI-PLC and PC-PLC via an upstream tyrosine kinase to induce PKC activation, then initiate the expression of iNOS and NO release. PKC isoform-a, -b1, -d, and -h were shown to be involved in the regulation of BSA-AGEs-induced iNOS expression. 縮寫詞彙 AGEs, advanced glycosylation end products. BSA-AGEs, bovine serum albumin derived advanced glycosylation end products NO, nitric oxide. iNOS, inducible nitric oxide synthase. PLC, phospholipase C. PI-PLC, phosphoinositide-specific phospholipase C. PC-PLC, phosphatidylcholine-specific phospholipase C. DAG, diacylglycerol. IP3, Inositol 1,4,5-trisphosphate. PIP2, phosphatidylinositol 4,5-bisphosphate . PKC, protein kinase C. RAGE, receptor for AGEs.