Objective To investigate the effects of silica dust on the expression of TLR4 mRNA and RelA mRNA in lung tissue of experimental mice.
Methods Forty mice were randomly divided into four groups with 10 mice in each group:control group (not exposed to silica dust), and 2, 4, and 8 h exposure groups (exposed to silica dust for 2, 4, and 8 h every day, respectively). After 20 days of exposure, lung tissues were dissected to detect the expression of TLR4 mRNA and RelA mRNA by RT-qPCR technology.
Results The median expression levels of TLR4 mRNA in the control group and three exposure groups were 0.89, 1.22, 4.89, and 7.21, respectively (χ2=4.93, P=0.02). Compared with the control group, the expression levels of TLR4 mRNA in the 4 h and 8 h exposure groups were both different (P < 0.05), but that in the 2 h exposure group showed no significant changes (P>0.05). The expression levels of RelA mRNA in the control group and three exposure groups were 0.96, 1.33, 2.23, and 3.04, respectively (χ2=6.35, P=0.00). Compared with the control group, the expression levels of RelA mRNA in the 4 h and 8 h exposure groups were both significantly different (P < 0.05), but that in the 2 h exposure group showed no significant changes (P>0.05). The expression levels of TLR4 mRNA and RelA mRNA showed a significant correlation (r=0.99, P=0.00).
Conclusion The elevated expressions of TLR4 mRNA and RelA mRNA in the lung tissue of mice exposed to silica dust indicate the activation of TLR4/RelA signaling pathway.
DownLoad: