Exploring the Toxicological Effects of Silver Nanoparticles: Oxidative Stress and Neurodegenerative Disorders

Silver nanoparticles (AgNPs) is used in many industries due to their exclusive antibacterial, antiviral, antiproliferative, and tissue-engineering properties. Toxicological concerns of these nanoparticles was raised due to their accumulation in many organs where they can induce oxidative stress and inflammation. This study aims to study the toxicological effects of AgNPs through biochemical and molecular analysis.ROS produced by the presence of AgNPs compromises antioxidant resistance, translocate and cross biological barriers, like the blood-brain barrier (BBB), and accumulate in brain tissues, leading neurodegenerative disorders.In this study, Wistar male rats were injected intraperitoneally to different doses of AgNPs doses over a three-week period to test both acute and chronic toxicity. Four groups of rats were divided as following: a control group treated with saline and three treatment groups receiving different doses of AgNPs (500 mg/kg for acute, 50 mg/kg, and 30 mg/kg for chronic exposure). Rats’ body weights were measured at the end of treatment, blood samples were collected for hematological analysis. Furthermore, the liver and brain tissues were used to examine the presence of AgNPs in cells.Biochemical tests conducted included measurements of total leukocyte count, erythrocyte count, hemoglobin levels, hematocrit, and red blood cell indices. Liver function tests were conducted along with assessments of antioxidant enzyme activities, such as glutathione S-transferase (GST), glutathione peroxidase (GPx), catalase (CAT), and glutathione (GSH) levels, in addition to evaluating lipid peroxidation through thiobarbituric acid reactive substances (TBARS). In the brain, acetylcholinesterase (AChE) activity and Na+/K+ ATPase activity were measured to assess the neurological impacts of AgNP exposure.The study’s results indicate that AgNPs increased oxidative stress markers and induced cellular damage as indication of cytotoxicity. This confirmed the potential toxicological effect of AgNP, especially for nervous system. These findings underscore the further research to determine safe exposure limits the use of AgNPs.