GSE136945
Tobacco smoke exposure exacerbates silica-induced pulmonary toxicity in rats
Previous studies have shown that smoking induces oxidative stress and inflammation, known factors that coincide with the development and progression of silicosis.  Nevertheless, the precise role of cigarette smoke exposure in silicosis and the underlying mechanisms are not clearly understood. Therefore, the objective of the present study was to determine the effect of smoking, if any, on silica-induced pulmonary response and the underlying mechanisms. Pulmonary toxicity and lung gene expression profiles were determined in male Fischer 344 rats exposed to air, crystalline silica, cigarette smoke or cigarette smoke plus crystalline silica. Silica exposure resulted in significant pulmonary toxicity which was further exacerbated by cigarette smoke exposure in the rats. Significant differences in the gene expression profiles were detected in the lungs of the rats exposed to cigarette smoke, silica or a combination of both compared with the control rats. Overall design: Lung RNA profiles of rat exposed to air, crystalline silica, cigarette smoke, or cigarette smoke and crystalline silica were generated by deep sequencing, in sextuplate, using Illumina HiSeq.