UV-aged polystyrene nanoplastics aggravate intestinal barrier damage by overproduction of ROS.

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.

New Sight of Renal Toxicity Caused by UV-Aged Polystyrene Nanoplastics: Induced Ferroptosis via Adsorption of Transferrin.

Secondary nanoplastics (NPs) caused by degradation and aging due to environmental factors are the main source of human exposure, and alterations in the physicochemical and biological properties of NPs induced by environmental factors cannot be overlooked. In this study, pristine polystyrene (PS) NPs to obtain ultraviolet (UV)-aged PS NPs (aPS NPs) as secondary NPs is artificially aged. In a mouse oral exposure model, the nephrotoxicity of PS NPs and aPS NPs is compared, and the results showed that aPS NPs exposure induced more serious destruction of kidney tissue structure and function, along with characteristic changes in ferroptosis. Subsequent in vitro experiments revealed that aPS NPs-induced cell death in human renal tubular epithelial cells involved ferroptosis, which is supported by the use of ferrostatin-1, a ferroptosis inhibitor. Notably, it is discovered that aPS NPs can enhance the binding of serum transferrin (TF) to its receptor on the cell membrane by forming an aPS-TF complex, leading to an increase in intracellular Fe2+ and then exacerbation of oxidative stress and lipid peroxidation, which render cells more sensitive to ferroptosis. These findings indicated that UV irradiation can alter the physicochemical and biological properties of NPs, enhancing their kidney biological toxicity risk by inducing ferroptosis.

Short term exposure to polystyrene nanoplastics in mice evokes self-regulation of glycolipid metabolism.

With the detection of nano-plastics (NPs) in daily essentials and drinking water, the potential harm of NPs to human health has become the focus of global attention. Studies have shown that long term exposure to NPs can lead to disorders of glucose and lipid metabolism in organisms, while the effects of short term exposure are rarely reported. Moreover, environmental factors cause the aging of NPs, and it is unclear whether this has an effect on their toxicity. In this study, we use 100 nm polystyrene (PS) NPs and ultraviolet (UV) aging PS (aPS) NPs to gavage mice for 7 days at an exposure dose of 50 mg/kg/day. To evaluate the effects of exposure on mice hepatic glucose lipid metabolism, we performed blood biochemical, pathological and metabolomic analyses. The results showed that exposure to PS NPs and aPS NPs increased serum glucose, disrupted serum lipoprotein levels, and up-regulated the expression levels of phosphatidylinositol 3-kinase (PI3K)/ phosphoprotein kinase B (p-AKT)/Glucose transporter 4 (GLUT4) proteins in the glucose metabolism pathway. The expression levels of key proteins sterol regulatory element binding protein-1 (SREBP-1)/peroxisome proliferator-activated receptor-γ (PPARγ)/adipose triglyceride lipase (ATGL) in the lipid metabolism signaling pathway were significantly increased. These findings suggest that short term exposure to PS NPs and aPS NPs induces glycolipid metabolism disturbance in mice, which may subsequently awaken the mice to self-regulate the serum levels of various lipoproteins and the expression of related key proteins. Compared with PS NPs, the aPS NPs interfered more strongly with glucose metabolism, and the corresponding self-regulation in mice was also more obvious. These findings not only provide a basis for environmental factors to increase the health risk of NPs but also provided a reference for the selection of test substances for further studies on the toxicity of NPs.

A novel insight into mechanism of derangement of coagulation balance: interactions of quantum dots with coagulation-related proteins.

BACKGROUND: Quantum dots (QDs) have gained increased attention for their extensive biomedical and electronic products applications. Due to the high priority of QDs in contacting the circulatory system, understanding the hemocompatibility of QDs is one of the most important aspects for their biosafety evaluation. Thus far, the effect of QDs on coagulation balance haven't been fully understood, and limited studies also have yet elucidated the potential mechanism from the perspective of interaction of QDs with coagulation-related proteins. RESULTS: QDs induced the derangement of coagulation balance by prolonging the activated partial thromboplastin time and prothrombin time as well as changing the expression levels of coagulation and fibrinolytic factors. The contact of QDs with PTM (prothrombin), PLG (plasminogen) and FIB (fibrinogen) which are primary coagulation-related proteins in the coagulation and fibrinolysis systems formed QDs-protein conjugates through hydrogen-bonding and hydrophobic interaction. The affinity of proteins with QDs followed the order of PTM > PLG > FIB, and was larger with CdTe/ZnS QDs than CdTe QDs. Binding with QDs not only induced static fluorescence quenching of PTM, PLG and FIB, but also altered their conformational structures. The binding of QDs to the active sites of PTM, PLG and FIB may promote the activation of proteins, thus interfering the hemostasis and fibrinolysis processes. CONCLUSIONS: The interactions of QDs with PTM, PLG and FIB may be key contributors for interference of coagulation balance, that is helpful to achieve a reliable and comprehensive evaluation on the potential biological influence of QDs from the molecular level.

An effective solution to simultaneously analyze size, mass and number concentration of polydisperse nanoplastics in a biological matrix: asymmetrical flow field fractionation coupled with a diode array detector and multiangle light scattering.

To accurately understand the biological pollution level and toxicity of polydisperse nanoplastics, an effective solution is presented to separate polydisperse nanoplastics and detect their size, mass and number concentration in a biological matrix by asymmetrical flow field fractionation coupled with a diode array detector and a multiangle light scattering detector.