Abstract：
UV irradiation significantly alters nanoplastics (NPs) physicochemical properties, thus affecting their biological toxicity. This study is the first to assess the influence of virgin and UV-aged polystyrene NPs (v-PS NPs, a-PS NPs) on the intestinal barrier of ICR mice. We found that a-PS NPs can cause more severe intestinal barrier damage compared with v-PS NPs. The reason may be attributed to that a-PS NPs produced more ROS in intestinal tissue. Moreover, the strong oxidizing property of hydroxyl radicals (·OH) generated from the a-PS NPs can damage cell membranes through lipid peroxidation, thereby leading to a low clearance rate of ·OH due to the impaired intestinal tissue function, in turn, causing more ROS to accumulate and inducing severe oxidative damage. This research underscores the crucial role of ·OH in mediating oxidative damage from UV-aged nanoparticles, emphasizing the need to consider environmental factors in assessing NPs toxicity.
摘要：
紫外线照射显著改变纳米塑料（NPs）的物理化学性质，从而影响其生物毒性。这项研究是第一个评估原始和紫外线老化的聚苯乙烯NP(v-PSNP，a-PSNPs)对ICR小鼠肠屏障的影响。我们发现，与v-PSNP相比，a-PSNP可引起更严重的肠屏障损伤。其原因可能归因于a-PSNP在肠组织中产生更多的ROS。此外，a-PSNP产生的羟基自由基(·OH)的强氧化性可通过脂质过氧化损伤细胞膜,因此，由于肠组织功能受损，导致·OH清除率低，反过来,导致更多的ROS积累并诱导严重的氧化损伤。这项研究强调了·OH在介导紫外线老化纳米粒子的氧化损伤中的关键作用，强调在评估NP毒性时需要考虑环境因素。
