Effect of exposure to silica in inducing autoimmune hepatitis: an experimental animal-controlled study

The aim of this experimental study is to investigate the effect of subcutaneous and oral sodium silicate in inducing the autoimmune hepatitis.

Twelve Brown Norway rats were studied, six rats were challenged with Sodium Silicate and the rest were challenged with normal saline as a control group. At 14th week post-sodium silicate or normal saline exposure, the rats were sacrificed. Histopathological studies were conducted in six positive autoantibodies responding silicate group rats and then compared with an equal number of negative autoantibodies responding control rats.

The liver findings from sodium silicate group of animals showed a histopathological reaction in 3/6 (50%) compared with 0/6 of the corresponding control saline group (p = 0.09). However, the absolute differences in the percentage between the two groups was 50%, the subcutaneous sodium silicate sub-group showed hepatic tissue response close to being statistically significant level (p = 0.05).

After correlating the results with autoantibodies including serum antinuclear antibodies and anti ribo-nucleoprotein response of the same rats, it is concluded that sodium silicate play a role in inducing the autoimmune hepatitis in a genetically susceptible rat model.