Nickel-refining dust regulates the expression of inflammatory factors in NIH/3T3 cells

Nickel (Ni) is a metal known to be a human carcinogen that occupational workers can be exposed to during the process of Ni refining. We investigated the molecular mechanism of inflammation that is induced by Ni-refining dust in a factory, using concentrations of 0, 25, 50, and 100 µg/mL for 24 h and 48 h, in vitro. Quantitative real-time polymerase chain reactions (qRT-PCR), Western blot analysis, and enzyme-linked immunosorbent assays (ELISA) were used to detect the transcriptional expression levels of nuclear factor-κB (NF-κB), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). Results showed that Ni-refining dust decreased the secretion of IL-6 under the experimental conditions. In contrast, Ni-refining dust activated NF-κB expression and stimulated the secretion of TNF-α, IL-1β, iNOS, and COX-2 in a dose- and time-dependent manner. To summarize, we demonstrated that exposure to Ni-refining dust can induce the expression of NF-κB in NIH/3T3 cells and the secretion of inflammation related factors. This provides a new basis for further study of the inflammatory effects of Ni-refining dust.