Impact of Dietary nanoparticles on the composition and function of the gut microbiota in mice - impact of long-term ingestion (24 weeks). Dietary nanoparticles on the mice gut

Nanotechnologies provide new opportunities for improving the safety, quality, shelf life, flavor and aspect of foods. The most common dietary nanoparticles (NPs) are silver present in some food packaging, and silicon and titanium dioxides both used as additives. The rapid development and commercialization of consumer products containing engineered NPs is, however, not sufficiently supported by toxicological studies and risk assessment. Disruption of the gut microbiota (GM) and/or local and systemic toxicity have already been observed after oral administration of NPs in experimental animals, but results are not consistent, and doses used were often much higher than the currently estimated human intakes. In view of the strong evidence that links alterations of the GM to cardiometabolic (CM) diseases, we hypothesized that food NPs might disturb this GM-CM axis. Thus, we assessed in male C57BL/6JRj mice the impact of long-term ingestion (24 weeks) of Ag (0, 4, 40 or 400 μg/kg pellet), SiO2 (0, 0.8, 8 and 80 mg/kg pellet) or TiO2 (0, 0.4, 4 or 40 mg/kg pellet) NPs on the GM and CM status. The reversibility of the effects was examined after 8 additional weeks without NPs intake (recovery period).

纳米技术为提升食品的安全性、品质、保质期、风味与外观提供了全新机遇。膳食来源纳米颗粒（nanoparticles, NPs）中最为常见的品类包括部分食品包装中使用的银，以及作为添加剂应用的二氧化硅与二氧化钛。然而，含工程化纳米颗粒的消费品快速发展与商业化进程，尚未获得足够的毒理学研究与风险评估支撑。已有研究在经口给予纳米颗粒的实验动物体内，观察到肠道菌群（gut microbiota, GM）紊乱以及局部或全身毒性反应，但相关研究结果并不一致，且所用剂量往往远高于当前估算的人体摄入量。鉴于已有充分证据表明肠道菌群紊乱与心脏代谢（cardiometabolic, CM）疾病存在关联，本研究提出假设：食品来源纳米颗粒可能会扰乱这一肠道菌群-心脏代谢轴。为此，本研究以雄性C57BL/6JRj小鼠为模型，评估了长期（24周）摄入银（Ag，剂量设置为0、4、40或400 μg/kg饲料）、二氧化硅（SiO₂，剂量设置为0、0.8、8或80 mg/kg饲料）或二氧化钛（TiO₂，剂量设置为0、0.4、4或40 mg/kg饲料）纳米颗粒对其肠道菌群与心脏代谢状态的影响。在额外8周无纳米颗粒摄入的恢复期后，本研究同时考察了上述效应的可逆性。