Histopathological effects of nanosilver (Ag-NPs) in liver after dermal exposure during wound healing

With the advent of nanotechnology, significant progress has been made in the area of nanoscale materials such as nanosilver (Ag-Nps). These nanoparticles have a wide range of applications and been used for antimicrobial purposes for more than a century. However, little attention has been paid to the toxicity of nanosilver wound dressing. This study was designed to investigate the possible histopathological toxicity of Ag-NPs in liver of mice during wound healing. A group of 50 female BALB/c mice of about 8 weeks were randomly divided into two groups: Ag-NPs and control groups (n=25). After creating similar wound on the backs of all animals, the wound bed was treated in Ag-NPs group, with a volume of 50 microliters of the nanosilver solution (10ppm), and in control group, with the same amount of distilled water. The experiment lasted for 14 days. Histopathaological samplings of liver were conducted on days 2, 7 and 14 of the experiment. Histopathological studies demonstrated time-dependent changes in mice liver treated with Ag-NPs compared to control group. Some changes include dilation in central venous, hyperemia, cell swelling, increase of Kupffer and inflammatory cells. This study suggests that use of nanosilver for wound healing may cause a mild toxicity, as indicated by time-dependent toxic responses in liver tissue. However, this issue will have to be considered more extensively in further studies.