[Effect of Gymnadenia conopsea alcohol extract on pulmonary fibrosis of rats exposed to silica and the expression of tumor necrosis factor-alpha].

OBJECTIVE

To study the roles of Gymnadenia conopsea alcohol extract on pulmonary fibrosis of rats exposed to silica and the expression of TNF-alpha.

METHODS

The 120 Wistar rats were randomly divided into control group, silica group and gymnadenia conopsea alcohol extract combined with SiO2 group (combined group). Silica was injected intratracheally to the rats of silica group and combined group, while mitte tales doses physiological saline was injected intratracheally to the rats of control group. Gymnadenia conopsea alcohol extract 2ml (10g/kg) were intragastric administrated to the rats of combined group every day after silica was injected intratracheally to the rats one day, however mitte tales doses physiological saline were intragastric administration to the rats of control group and silica group. I and III collagen were detected by sirius red polarization microscopy. TNF-alpha proteins in paraffin-embedded lung sections were immunohistochemistrily stained on tissue microarray with PV method.

RESULTS

In comparison with those of silica groups, the coefficient of lung organ to body of rats in combined groups decreased significantly (P < 0.01). In comparison with those of silica groups, I collagens of combined groups decreased (P < 0.01) and III collagen decreased significantly at the 14th and 21st day (P < 0.05, P < 0.01). The integrated optical densities of TNF-alpha expression in the lung tissue of combined group reduced (P < 0.01) in comparison with those of silica groups.

CONCLUSIONS

Gymnadenia conopsea alcohol extract could inhibit pulmonary fibrosis and the expression of TNF-alpha in lung tissue of rats exposed to silica.