Background: Gold nanoparticles are associated with oxidative stress due to free radical production. Antioxidants can reduce the damaging effects of free radicals in the long-term. Given the importance of enhanced oxidative stress in the incidence of tissue damage by nanoparticles and the role of silymarin in reducing oxidative stress index, this study was conducted to evaluate the protective and antioxidant effects of silymarin on male rats treated with gold nanoparticles. In this study, 32 male Wistar rats (250-350 g) were divided into four groups: one control group and three intervention groups. The intervention groups included a group receiving 100 ppm gold nanoparticles, a group fed with 200 mg/kg silymarin, and a group receiving the same doses of gold nanoparticles and silymarin. All injections were performed intraperitoneally for a period of 4 consecutive weeks (28 d).
Result: Levels of catalase (CAT), glutathione peroxidase (GPX), and malondialdehyde (MDA) of red blood cells were measured. Data was analyzed using ANOVA and Bonferroni tests. In the animals treated with gold nanoparticles the MDA concentration significantly increased while a significant decrease was seen in GPX and CAT activities (P<0.05). Also, silymarin extract significantly reversed these effects and the group receiving both silymarin and gold nanoparticles had increased GPX and CAT activities and decreased MDA concentration (P<0.05), as compared to the group receiving gold nanoparticles alone.
Conclusion: Overall, our results suggest that silymarin decreases the toxicity induced by gold nanoparticle in diabetic rats and can be considered for further treatment studies.