Glycated human serum albumin enhances macrophage inflammatory protein-1β mRNA expression through protein kinase C-δ and NADPH oxidase in macrophage-like differentiated U937 cells

详细信息    查看全文

• 作者：Koji Higai ; Misaki Satake ; Haruka Nishioka ; Yutaro Azuma ; Kojiro Matsumoto
• 关键词：Glycated albumin ; MIP ; NADPH oxidase ; Protein kinase C ; NFκ ; B ; AP-1
• 刊名：Biochimica et Biophysica Acta (BBA)/General Subjects
• 出版年：2008
• 出版时间：February 2008
• 年：2008
• 卷：1780
• 期：2
• 页码：307-314
• 全文大小：722 K

文摘

In a previous report (Higai K et al., Biol Pharm Bull, 2007), glycated human serum albumin (Glc-HSA) was found to induce interleukin-8 (IL-8) mRNA expression in human monocyte-derived U937 cells through a reactive oxygen species (ROS)-dependent pathway; however, Glc-HSA signaling has not been elucidated in macrophages.

Methods:

U937 cells were differentiated by treatment with 50 ng/mL phorbol 12-myristate 13-acetate (PMA) for 2 days and the macrophage-like differentiated U937 (differentiated U937) cells were stimulated with Glc-HSA and glycolaldehyde dimer-modified HSA (GA-HSA) in the presence of various signaling inhibitors. Macrophage inflammatory protein-1β (MIP-1β) mRNA expression was determined by real-time PCR. Intracellular ROS generation was estimated by confocal laser microscopy.

Results:

Glc-HSA and GA-HSA markedly enhanced MIP-1β mRNA expression in differentiated U937 cells. Enhanced MIP-1β mRNA expression was completely suppressed by the ROS scavenger N-acetyl-l-cysteine, the NADPH oxidase inhibitors diphenylene iodonium and apocynin, and the protein kinase C (PKC)-δ inhibitor rottlerin. Furthermore, ROS generation was suppressed completely by rottlerin but not by the PKC-γ inhibitor Ro318425 or the PKC-α, -β1 and -μ inhibitor Go6976.

Conclusion:

Glc-HSA and GA-HSA enhance MIP-1β mRNA expression in differentiated U937 cells through PKC-δ-dependent activation of NADPH oxidase.