Methylmercury induces CCL2 expression through activation of NF-κB in human 1321N1 astrocytes

Methylmercury is an environmental pollutant that is toxic to the central nervous system; however, the molecular mechanisms underlying its toxicity remain unclear. Methylmercury increases expression of several chemokines in the cerebellum of mice treated with methylmercury. The present study analyzes the mechanism underlying methylmercury-induced chemokine expression using human 1321N1 astrocytes, and shows that methylmercury increases CCL2 expression in these cells. The transcription factor NF-κB is involved in the induction of chemokine expression. Methylmercury increased the level of the NF-κB p65 subunit in the nuclei of 1321N1 cells. The methylmercury-induced increase in CCL2 expression was significantly decreased by suppression of p65 expression by RNA interference. These results suggest that methylmercury induces chemokine expression through activation of NF-κB in human astrocytes.