Stimulation of Alpha7 Nicotinic Acetylcholine Receptor Attenuates Nicotine-Induced Upregulation of MMP, MCP-1, and RANTES through Modulating ERK1/2/AP-1 Signaling Pathway in RAW264.7 and MOVAS Cells

Figure 2

U0126 attenuated nicotine-induced activations of extracellular signal-regulated kinase1/2 (ERK1/2) and c-Jun and upregulation of matrix metalloproteinase- (MMP-) 9, MMP-2, monocyte chemotactic protein- (MCP-) 1, and regulated upon activation normal T cell expressed and secreted (RANTES) in RAW264.7 cells. (a) RAW264.7 cells were pretreated with 10 μm and 20 μm U0126 for 30 min prior to 10 ng/ml nicotine exposure for 30 min. (d) RAW264.7 cells were pretreated with 10 μm and 20 μm U0126 for 30 min prior to 10 ng/ml nicotine exposure for 3 h. (b, c, e–h) The intensity of protein bands (means ± SD) in the Western blot were quantified by using ImageJ software and normalized to GAPDH. Representative results from three independent experiments are shown. (i) MMP-9, (j) MMP-2, (k) MCP-1, and (l) RANTES mRNA levels were determined by real-time reverse transcription polymerase chain reaction. All experiments were analyzed as triplicate independent experiments. and versus controls; ^# and ^## versus the group treated with nicotine.

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