Neurotoxicity of silver nanoparticles in the animal brain: a systematic review and meta-analysis.

Autor: Janzadeh A; Radiation Biology Research Center, Iran University of Medical Sciences, Tehran, Iran., Behroozi Z; Department of Physiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran., Saliminia F; Department of Medical Nanotechnology, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran., Janzadeh N; Occupational Medicine Research Center (OMRC), Iran University of Medical Sciences (IUMS), Tehran, Iran., Arzani H; Department of Medical Physics and Biomedical Engineering, Shahid Beheshti University of Medical Sciences, Tehran, Iran.; Research Center of Advanced Technologies in Medicine, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran., Tanha K; Department of Biostatistics, School of Public Health, Iran University of Medical Sciences, Tehran, Iran., Hamblin MR; Laser Research Centre, Faculty of Health Science, University of Johannesburg, Doornfontein, 2028, South Africa. hamblin.lab@gmail.com., Ramezani F; Physiology Research Center, Iran University of Medical Sciences, Tehran, Iran. Ramezani.f@iums.ac.ir.
Jazyk: angličtina
Zdroj: Forensic toxicology [Forensic Toxicol] 2022 Jan; Vol. 40 (1), pp. 49-63. Date of Electronic Publication: 2021 Jul 29.
DOI: 10.1007/s11419-021-00589-4
Abstrakt: Objective: About 30% of all nanoparticle products contain silver nanoparticles (AgNPs). With the increasing use of AgNPs in industry and medicine, concerns about the adverse effects on the environment, and the possible toxicity of these particles to primary cells and towards organs such as the brain and nervous system increased. In this paper, the toxicity of AgNPs in neurons and brain of animal models was investigated by a systematic review and meta-analysis.
Methods: The full texts of 26 relevant studies were reviewed and analyzed. Data from nine separate experiments in five articles were analyzed by calculating the standardized mean differences between viability of treated animals and untreated groups. Subgroup analysis was conducted. In addition, a systematic review provided a complete, exhaustive summary of all articles.
Results: The results of the meta-analysis showed that AgNPs are able to cause neuronal death after entering the brain (standardized mean difference (SMD) = 2.87; 95% confidence interval (CI) 2.1-3.61; p < 0.001). AgNPs sized smaller or larger than 10 nm could both cause neuronal cell death. This effect could be observed for a long time (up to 6 months). Neurons from embryonic animals whose mothers had been exposed to AgNPs during pregnancy were affected as much as animals that were themselves exposed to AgNPs. Toxic effects of AgNPs on memory and cognitive function were also observed. Studies have shown that inflammation and increased oxidative stress followed by apoptosis are likely to be the main mechanisms of AgNPs toxicity.
Conclusion: AgNPs can enter the brain with a long half-life and it can cause neuronal death after entering the brain. AgNPs can manifest proinflammatory cascades in the CNS and BBB. Some toxic effects were detected in the cerebral cortex, hypothalamus, hippocampus and others. Studies have shown that inflammation and increased oxidative stress lead to apoptosis, the main mechanism of AgNPs neurotoxicity, which can be caused by an increase in silver ions from AgNPs.
(© 2021. Japanese Association of Forensic Toxicology.)
Databáze: MEDLINE
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