Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, 100191, People's Republic of China.
Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety, School of Public Health, Peking University, Beijing, 100191, People's Republic of China.
Arch Toxicol. 2023 Aug;97(8):2051-2067. doi: 10.1007/s00204-023-03536-x. Epub 2023 Jun 22.
Numerous studies in recent years have questioned the safety of oral exposure to titanium dioxide nanoparticles (TiO NPs). TiO NPs are not only likely to accumulate in the gastrointestinal tract, but they are also found to penetrate the body circulation and reach distant organs. The liver, which is considered to be a target organ for nanoparticles, is of particular concern. TiO NPs accumulate in the liver and cause oxidative stress and inflammatory reactions, resulting in pathological damage. The impact of TiO NPs on liver aspartate aminotransferase (AST) and alanine aminotransferase (ALT) was studied using a meta-analysis. According to the findings, TiO NPs exposure can cause an elevation in AST and ALT levels in the blood. Furthermore, TiO NPs are eliminated mostly through feces, and their lengthy residence in the gut exposes them to microbiota. The gut microbiota is also dysbiotic due to titanium dioxide's antibacterial capabilities. This further leads to changes in the amount of microbiota metabolites, which can reach the liver with blood circulation and trigger hepatotoxicity through the gut-liver axis. This review examines the gut-liver axis to assess the effects of gut microbiota dysbiosis on the liver to provide suggestions for assessing the gut-hepatotoxicity of TiO NPs.
近年来，许多研究质疑了口服摄入二氧化钛纳米颗粒（TiO NPs）的安全性。TiO NPs 不仅可能在胃肠道中积累，而且还被发现穿透体循环并到达远处的器官。肝脏被认为是纳米颗粒的靶器官，因此尤为令人关注。TiO NPs 在肝脏中积累，导致氧化应激和炎症反应，从而造成病理性损伤。本研究采用荟萃分析探讨了 TiO NPs 对肝脏天冬氨酸氨基转移酶（AST）和丙氨酸氨基转移酶（ALT）的影响。研究结果表明，TiO NPs 暴露可导致血液中 AST 和 ALT 水平升高。此外，TiO NPs 主要通过粪便排出，而其在肠道中的长时间停留使其暴露于微生物群中。由于二氧化钛具有抗菌能力，肠道微生物群也会出现失调。这进一步导致微生物群代谢物的数量发生变化，这些代谢物可以随血液循环到达肝脏，并通过肠-肝轴引发肝毒性。本综述探讨了肠-肝轴，以评估肠道微生物群失调对肝脏的影响，为评估 TiO NPs 的肠道-肝毒性提供建议。
