Silica dust alters fecal microbiota that contributes silciosis through the lung-gut axis in rats
Background:Silicosis is a lung disease with diffuse nodular pulmonary fibrosis because of long-term inhalation of a large number of free silica dust. Research has been reported that dysbiosis of fecal microbiota was existed in silicosis patients. However, few studies have examined the effects of silica on the intestinal tract.  Objective: In this study, we aimed to investigate the interaction between fecal microbiota and ileum injury at tissue and molecular level after silica exposure and predict the potential mechanism.  Methods: The wistar male rats were intratracheally instilled with 50 mg/mL silicon dioxide (1 mL per rat). We observed the changes of pulmonary inflammation, fibrosis and ileum tissues. Then, we employed fecal microbiota transplantation (FMT) experiment to examine whether fecal microbiota paly the important roles in the change of silica-induced pulmonary inflammation, fibrosis and ileum injury. Finally, the differential microbiota and metabolites of faeces, and mRNAs of ileum were detected after 56 days.