Maleylated-BSA induces TNF-α production through the ERK and NF-κB signaling pathways in murine RAW264.7 macrophages

Abstract

Ligands for macrophage scavenger receptors are reported to induce a wide range of host cell responses, including the production of inflamma tory cytokines; however, the underlying mechanisms have not yet been fully understood and which remain obscure. In this study, we have examined the effect of maleylated bovine serum albumin (maleylated-BSA), a well-known ligand of the scavenger receptor, on the murine macrophage cell line RAW264.7. Maleylated-BSA strongly induced the production of tumor necrosis factor- α (TNF- α ) and induced phosphorylation of extracellular signal-regulated kinase (ERK) and NF- k B p65. We also observed that maleylated-BSA-induced TNF- α production was blocked by the ERK inhibitor U0126. Together, these data demonstrates that maleylated-BSA- induced production of TNF- α requires the ERK/NF- κ B signaling cascade in murine RAW- 264.7 macrophages.