Histological Assessment of Brain Tissue Following Exposure to Magnesium Oxide Nanoparticles

Magnesium oxide nanoparticles (MgO NPs) are increasingly utilized in biomedical, pharmaceutical, and industrial fields because of their distinctive physicochemical characteristics. Despite their widespread applications, concerns persist regarding their potential neurotoxic effects and overall biological safety. This study aimed to evaluate the neurotoxic impact of MgO nanoparticles on brain tissue in male Sprague-Dawley rats and to determine the influence of dose and exposure duration on tissue damage. Fifty-four adult male Sprague-Dawley albino rats were randomly assigned to nine groups, comprising one control group and eight treatment groups. Treated animals received 1 mL of MgO NP suspension by oral gavage at either a low dose (250 mg/kg) or a high dose (1000 mg/kg) for periods of 14, 28, or 56 days. At the end of each treatment period. Early exposure to MgO nanoparticles induced lipid accumulation, reduction of cerebral nerve fibers, neuronal degeneration, and apoptotic changes affecting both neurons and neuroglial cells. With prolonged exposure, the severity of tissue damage increased markedly, characterized by extensive apoptosis of neuronal and neuroglial cells, greater deposition of lipid complexes, and a pronounced loss of cerebral cortex nerve fibers. These pathological changes indicate progressive deterioration of brain architecture associated with increasing dose and exposure duration. The findings suggest that MgO nanoparticles can exert significant adverse effects on brain tissue and may represent a potential risk to neurological health. Further investigations are required to elucidate the mechanisms underlying MgO NP-induced neurotoxicity and to establish safe exposure limits for biomedical and consumer applications.