Titanium dioxide nanoparticles (TiO2NPs) are manufactured worldwide for various bioengineering applications. They are frequently used in medicine, in sun protection creams, and in industries such as paints. However, these nanoparticles can induce pulmonary toxicity and its mechanism and prevention is not fully understood.Objective
This study aimed to investigate the effect of TiO2NPs on histological structure of the lung and the possible protective role of milk thistle extract.Materials and methods
The present study was carried out on 30 adult male rats divided into three groups: group I, which served as a control; group II, in which rats were intraperitoneally injected with 150 mg/kg/day TiO2NPs for 2 weeks; and group III, in which rats were treated with milk thistle extract and TiO2NPs. The lung specimens were dissected out and processed for histological and immunohistochemical studies.Results
After 2 weeks of TiO2NPs treatment, collapsed alveoli with loss of normal architecture were detected. Relatively thick interalveolar septa with cellular infiltration were also noticed. Type II pneumocytes showed degenerative changes with significant increase in their number. In addition, numerous deposited collagen fibers were detected. Immunohistochemical analysis revealed significant increase in the mean number of positive anti- vimentin and proliferating cell nuclear antigen-immunostained cells. Combined treatment with milk thistle extract and TiO2NPs led to marked improvement in most of the previously mentioned changes with significant decrease in the vimentin and proliferating cell nuclear antigen immunoreactivity.Conclusion
Milk thistle seed extract supplementation can prevent TiO2NPs lung toxicity.