Titanium dioxide (TiO2) nanoparticles have biological effects that may be caused by fibrosis or emphysema through effects on matrix metalloproteinase expression. The aim of this study investigates the effect of TiO2 nanoparticles on MMP-12 expression. Sixty-three rats were intratracheally instilled with (0.5, 1.5, 5, 15, 50, 150) mg/kg body weight of TiO2 nanoparticles for 4 weeks. Animals were sacrificed at 4 days, a month and 3 months post-instillation, immunohistochemistry of MMP-12 antibody and lung mRNA of MMP-12 gene expression. At 4 days post-instillation, TiO2 nanoparticles decreased macrophage MMP-12 expression with emphysema at high doses and fibrosis at low doses caused fibrosis while after a month and 3 months post-instillation macrophage MMP-12 increased and induce pulmonary response with emphysema at low doses. TiO2 nanoparticles aggravated elastase-induced emphysema and caused histological inflammation and downregulate MMP-12 mRNA expression and protein expression in macrophage and matrix extracellular.
 

Download Full Text - PDF