Diosgenin ameliorates silica-induced tuberculosis in rats

Silicosis is an occupational lung disease that is caused by chronic exposure to silica dust. Silica-exposed workers are at higher risk of developing TB, resulting in lung fibrosis and significant respiratory dysfunction. Diosgenin is a steroidal saponin that has been shown to exert a therapeutic effect on lung injury. Therefore, we investigated the potential efficacy of diosgenin in treating silicotuberculosis by evaluating its effectiveness against Mycobacterium smegmatis, as well as its antifibrotic and antioxidant effects in silica-induced TB in rats.

Silicosis was induced by intratracheal instillation of 50 mg/kg crystalline silica in Sprague-Dawley rats. Rats were grouped into 7 (10 per group). Different doses of diosgenin (1, 10, and 20 mg/kg) and saline were administered for 30 days. Afterwards, five rats from each group were sacrificed, and the five remaining rats in each group, except the control, received Mycobacterium smegmatis. Treatment continued until the 50th day, and the animals were sacrificed at the end of the experiment. The result was analyzed using a one-way analysis of variance (ANOVA) with GraphPad Prism.

At a half-maximal inhibition concentration of 0.006043 μg/mL, diosgenin inhibited the growth of Mycobacterium smegmatis. Oxidative stress markers such as malondialdehyde were significantly reduced. The health-enhancing effects of catalase and superoxide dismutase were elevated. Additionally, histological findings demonstrated a significant improvement in respiratory function following diosgenin treatment.

Diosgenin treatment inhibited the growth of Mycobacterium smegmatis, leading to a reduction in the susceptibility of rats to infection and improved pulmonary function through its antioxidant effect.