Synopsis
The purpose of this study was to analyze the effects of lipopolysaccharide (LPS)-stimulation and IC50 nickel (Ni) (2+) ions on gene expressions of mouse macrophage-like cell line RAW264 cultured in 10% serum-supplemented a-MEM employing 32k DNA microarray. The results revealed that two stimulants (LPS and IC50 Ni (2+) ions) up-regulated genes of inflammatory mediators quite differently. LPS stimulation (4 h) caused RAW264 to highly up-regulate 29 inflammation-related genes more than 20-fold, many of which were expressed by NF-kappaB cascade (e.g. Marker symbols =Il1a, Il1b, TNF, Csf3, Cxcl2, Ccl4 and Ptgs2). On the other hand, IC50 Ni (2+) ions (24 h) rendered RAW264 to moderately up-regulate 28 genes more than 8-fold, which included genes for chemokines (e.g. Cxcl2 and Ccl4), vascular endothelial growth factor (Vegfa), prostaglandin synthase (Ptgs2), anti-oxidant (Hmox1) and genome-damage-repair-factor (e.g. Hist1h2bc). Dual stimulation of LPS and IC50 Ni (2+) ions (4 h and 24 h) caused RAW264 to express mixed-mode gene expressions caused by two stimulants. RT-PCR experiments confirmed that relative expressions of four inflammation-related (TNFa, IL-1β, i-NOS and IL-6) genes of RAW 264 caused by two stimulants were in relatively good accordance with those clarified by DNA microarray analyses.
Key words: macrophage, DNA microarray, LPS, nickel ions, RT-PCR
