Pulmonary Exposure to Copper Oxide Nanoparticles Induces Systemic Inflammation, Oxidative Stress, and Prothrombotic Responses in BALB/c Mice.

Introduction: Copper oxide nanoparticles (CuONPs) are increasingly used in industrial and biomedical applications; however, their potential to provoke systemic vascular and hemostatic disturbances remains poorly defined. Methods: BALB/c mice were subjected to a single pulmonary instillation of CuONPs at doses of 3 µg or 30 µg per mouse, and the endpoints were evaluated 24 h post-exposure. Prior to biological testing, the CuONPs were characterized by X-ray diffraction, dynamic light scattering, zeta potential analyses and transmission electron microscopy, confirming their high crystallinity, relatively uniform particle size distribution and good electrostatic stability. Results: Exposure to CuONPs significantly shortened the thrombotic occlusion times in arterioles and venules; reduced prothrombin and activated partial thromboplastin times; and elevated plasma platelet factor 4, fibrinogen, plasminogen activator inhibitor-1, and C-reactive protein levels, indicating a shift toward a prothrombotic state. Oxidative stress is evidenced by increased levels of thiobarbituric acid-reactive substances, depleted glutathione levels, and decreased nitric oxide levels. In parallel, CuONPs induced significant upregulation of pro-inflammatory cytokines (tumor necrosis factor-α, interleukin (IL)-6, and IL-1β) and markers of DNA damage and apoptosis, including 8-hydroxy-2'-deoxyguanosine, cytochrome C release, and cleaved caspase-3 expression. Discussion: Collectively, these findings demonstrated that pulmonary exposure to low and high doses of CuONPs triggered systemic oxidative stress and inflammation, leading to prothrombotic responses, DNA damage, and apoptosis. This study highlights the potential vascular risks associated with CuONPs and underscores the importance of careful safety evaluation in biomedical and environmental contexts.