Cross-talk of the related bioactivity mediators in serum after injection of soluble TNF-α receptor on silicosis model of rats.

This study investigates cross-talk of the related bioactivity mediators in silica-induced pulmonary inflammatory and fibrosis on rats, which contributes to the preventive and therapeutic effect of soluble TNF-α receptor. Wistar rats received saline or 50 mg of quartz by intratracheal instillation. Rats in drug-treated groups were given soluble tumor necrosis factor-α (TNF-α) receptor (500 μg) by hypodermic injection on days 1, 5 and 8 after operation. At 7 days or 14 days after instillation, rats were killed to observe the degree of injury and expression of the related bioactivity mediators including nuclear factor KB (NF-KB), nitric oxide, interleukin-1β, interleukin-10, transforming growth factor beta 1 (TGF-β1), TNF-α, interferon-Y (IFN-Y) and granulocyte macrophage colony-stimulating factor (GM-CSF). The area percentages of type I and III collagens in intervention group were lower than those in silica group. The expression of NF-κB, TGF-β1, and COL I were lower in intervention group than in silica group(p < 0.05) and GM-CSF was significantly higher (p < 0.05) at 7 days after instillation, however, NF-κB, TGF-β1, and COL I were identically lower in intervention group than in silica group, and TNF-α, IFN-γ, and GM-CSF were higher at 14 days after instillation. It may be concluded that soluble TNF-α receptor upregulating or downregulating the expression of the related bioactivity mediators results in decreasing lung injury induced by silica.