Background and Objective: Recently, it has been shown that some naked metal nanoparticles have angiogenesis potential. In the present study, the anti-angiogenesis property of bare manganese oxide (MnO2) nanoparticles was investigated on chicken chorioallantoic membrane (CAM).
Materials and Methods: Fifty hen fertilized eggs were divided into five groups (n=10); the control and experimental groups treated with different concentration of MnO2 nanoparticles (1, 10, 100 ng and 1 μg). On the 8th day of incubation, a paper disk was placed on the chorionallantois membrane of eggs and soaked with PBS or different concentrations of the nanoparticles in control and treated groups, respectively. On the 10th day, all the cases were photographed using a photostereomicroscope. The number and the lengths of the vessels branching in microscopic images were quantified by Image J software.
Results: MnO2 nanoparticles at a concentration of 1ng in comparison with control had no significant effect on the mean number of blood vessels branching and its length. In contrast, application of the nanoparticles at concentrations of 10, 100 ng and 1 μg, progressively (p<0.01) reduced the measured parameters in CAM.
Conclusion: These results indicate potent anti-angiogenic activity of bare MnO2 nanoparticles. The nanoparticle is a potent oxidizing agent. Some metal oxide nanoparticles have shown cytotoxic and apoptotic effects on endothelial cells via induction of oxidative stress. Angiogenesis has been widely considered as an oxidative stress condition. So, the anti-angiogenesis activity of MnO2 nanoparticles in this model probably arises from the nanoparticles impact on the oxidative stress processes in CAM.
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