Effects of Particulate Matter 10 Inhalation on Lung Tissue RNA expression in a Murine Model

Abstract

Background: Particulate matter 10 (PM10; airborne particles <10 mu m) inhalation has been demonstrated to induce airway and lung diseases. In this study, we investigate the effects of PM10 inhalation on RNA expression in lung tissues using a murine model. Methods: Female BALB/c mice were affected with PM10, ovalbumin (OVA), or both OVA and PM10. PM10 was administered intranasally while OVA was both intraperitoneally injected and intranasally administered. Treatments occurred 4 times over a 2-week period. Two days after the final challenges, mice were sacrificed. Full RNA sequencing using lung homogenates was conducted. Results: While PM10 did not induce cell proliferation in bronchoalveolar fluid or lead to airway hyper-responsiveness, it did cause airway inflammation and lung fibrosis. Levels of interleukin 1 beta, tumor necrosis factor-alpha, and transforming growth factor-beta in lung homogenates were significantly elevated in the PM10-treated group, compared to the control group. The PM10 group also showed increased RNA expression of Rn45a, Snord22, Atp6v0c-ps2, Snora28, Snord15b, Snora70, and Mmp12. Generally, genes associated with RNA splicing, DNA repair, the inflammatory response, the immune response, cell death, and apoptotic processes were highly expressed in the PM10-treated group. The OVA/PM10 treatment did not produce greater effects than OVA alone. However, the OVA/PM10-treated group did show increased RNA expression of Clca1, Snord22, Retnla, Prg2, Tff2, Atp6v0c-ps2, and Fcgbp when compared to the control groups. These genes are associated with RNA splicing, DNA repair, the inflammatory response, and the immune response. Conclusion: Inhalation of PM10 extensively altered RNA expression while also inducing cellular inflammation, fibrosis, and increased inflammatory cytokines in this murine mouse model.