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With the increasing application of nanoparticles (NPs) in medical and consumer applications, it is necessary to ensure their safety. As m

Background: Arsenide, a kind of pollution widely existing in the environment, and the mechanism of occurrence and development of lung cancer leading by long-term arsenic exposure still needs further research up to present. We investigated how high and low doses of arsenic induce human bronchial epithelial cell transformation and the molecular mechanisms involvedMethods: After exposing human bronchial epithelial cells(Beas-2B) to different doses of sodium arsenite for 24 h, RNA-seq analysis was performed to detect arsenic-regulated genes; for cell viability and status and for cell cycle changes and mitochondrial function; long-term exposure to 1μM sodium arsenite after 20 consecutive passages for cell cycle changes and mitochondrial function.Results: In the study, human bronchial epithelial cells were exposed to varying high-dose sodium arsenite in short term or treated with low dose in a long term, and the data showed that both short and long terms treatment promoted G1/S transition of Beas-2B cells, inducing significant increases of expression of AKAP95, cyclin D1, cyclin D2 and cyclin E1. However, silencing AKAP95 by treating cells with siAKAP95 showed a protective function that inhibited G1/S transition, suggesting that regulatory mechanism of AKAP95 on cell cycle during cell malignant transformation induced by sodium arsenite. In addition, we also noticed some mitochondrial dysfunctions occurred during sodium arsenite exposure, including the disappearance of mitochondrial double membrane structure, the formation of vacuole structure, the decrease of mitochondrial membrane potential, the change of expression levels of mitochondrial related proteins Tim22, Tim23, Tom40 and OPA1, the release of lactate dehydrogenase (LDH) and the decrease of reduced glutathione.Beas-2B cells, which exposed to low-dose sodium arsenite for a long term, were subcultured for 20 generations, and it was found that the exposure time was positively proportional to the growth and migration rate of cells. The exposed cells were used in tumor bearing transplantation experiment (mice), and results showed that the longer the exposure time, the faster the tumor volume growth rate of As-Beas-2B cells. Tumor tissues were taken out for HE staining, and it was found that the cell morphology changed and the volume increasedConclusion: high and low doses of sodium arsenite induced malignant transformation of human bronchial epithelial cells by promoting G1/S turnover through AKAP95 with associated cyclins, accompanied by the development of mitochondrial dysfunction.

Arsenic is a widely existing pollutant in the environment, but the mechanism of occurrence and development of lung cancer by long-term arsenic exposure needs to be elucidated further. How the high and low doses of arsenic induce human bronchial epithelial cell transformation is yet to be elucidated. In the present study, human bronchial epithelial cells were exposed to varying high-dose sodium arsenite (NaAsO

Propylene glycol (PG; 1,2-propanediol) has been commonly used as a food additive and vehicle in pharmaceutical preparations. PG can form rectus (R-) enantiomers and sinister (S-) enantiomers. Herein, Kunming mice were used as the animal model to evaluate the acute and subacute oral toxicity of R-PG, S-PG and RS-PG (1:1 racemic mixture of R-PG and S-PG). The median lethal doses of R-PG, S-PG and RS-PG administered by oral gavage to mice were 22.81 g/kg, 26.62 g/kg and 24.92 g/kg, respectively. In the 28-day oral subacute toxicity study, the body weight, organ weights, serum biochemical, and renal histology were examined. There was no difference in subacute toxicity among R-PG, S-PG and RS-PG. The administration of 1 and 5 g/kg/day PG for 28 days caused nephrotoxicity. The kidney somatic index and levels of blood urea nitrogen exhibited a significant increase. Moreover, the activities of superoxide dismutase, catalase, and glutathione peroxidase significantly decreased after the treatment with PG. The levels of malondialdehyde, tumor necrosis factor α, interleukin 1β, and interleukin 6 significantly increased in the kidney. The results show that the nephrotoxic effects of PG are induced by oxidative stress, and the activation of the inflammatory response is mediated by the NF-κB signaling pathway. Together, these findings provide information on R-PG, S-PG and RS-PG treatments for the risk assessment of toxicity and effects on human health.

Mitophagy, a selective autophagy of mitochondria, clears up damaged mitochondria to maintain cell homeostasis. We performed high-content analysis (HCA) to detect the increase of PINK1, an essential protein controlling mitophagy, in hepatic cells treated with several nanoparticles (NPs). PINK1 immunofluorescence-based HCA was more sensitive than assays and detections for cell viability and mitochondrial functions. Of which, superparamagnetic iron oxide (SPIO)-NPs or graphene oxide-quantum dots (GO-QDs) was selected as representatives for positive or negative inducer of mitophagy. SPIO-NPs, but not GO-QDs, activated PINK1-dependent mitophagy as demonstrated by recruitment of PARKIN to mitochondria and degradation of injured mitochondria. SPIO-NPs caused the loss of mitochondrial membrane potential, decrease in ATP, and increase in mitochondrial reactive oxide species and Ca2+. Blocking mitophagy with PARKIN siRNA aggravated the cytotoxicity of SPIO-NPs. Taken together, PINK1 immunofluorescence-based HCA is considered to be an early, sensitive, and reliable approach to evaluate the bioimpacts of NPs.

Polychlorinated biphenyls (PCBs) are a class of persistent organic pollutants (POPs) that have adverse effects on human health. However, the long-term health effects and potential mechanism of neonatal exposure to PCBs are still unclear. In this study, nursing male mice exposed to PCB138 at 0.5, 5, and 50 μg/kg body weight (bw) from postnatal day (PND) 3 to PND 21 exhibited increased serum uric acid levels and liver uric acid synthase activity at 210 days of age. We also found an increased kidney somatic index in the 50 μg/kg group and kidney fibrosis in the 5 and 50 μg/kg groups. Mechanistically, PCB138 induced mitochondrial dysfunction and endoplasmic reticulum (ER) stress, which might have led to inflammatory responses, such as activation of the NF-κB (nuclear factor kappa-B) and NLRP3 (NOD-like receptor protein 3) pathways. The inflammatory response might regulate renal fibrosis and hypertrophy. In summary, this study reports a long-term effect of neonatal PCB exposure on uric acid metabolism and secondary nephrotoxicity and clarifies the underlying mechanism. Our work also indicates that early life pollutant exposure may be an important cause of diseases later in life.

Purpose: Cx43 (connexin 43) has been found to inhibit cell cycle of tumor cells. No nuclear localization sequence of Cx43 was found but the protein has been found in nucleus. The process remains unclear. We are aiming at providing the model that AKAP95 (A-kinase anchoring protein) binds to and transports Cx43 into nucleus of lung cancer cells.Methods: Lung cancer cells were arrested at preliminary stage (P), middle and late stage (M) of G1 phase and restriction point (R). Immunocoprecipitation (Co-IP) and Western blot (WB) were used to analyze expression and binding of AKAP95, Cx43, cyclin D1 and cyclin E1 at different stages of lung cancer cells during G1 phase. Confocal laser scanning microscopy (CLSM) was used to detect the location of proteins in arrested cells. Transmission electron microscope (TEM) with higher resolution was used to detect binding/aggregating and location of the above four proteins at subcellular level.Results: 1) AKAP95 transports Cx43 into the nucleus through the nuclear pore mainly at R stage. Some AKAP95 and Cx43 form protein aggregates during the process. 2) Cyclin E1 was found to be bind/aggregate with AKAP95-Cx43 complex and involved in the nuclear transport of Cx43 mainly at R stage. 3)Cyclin D1 was found to bind with AKAP95 and Cx43 respectively but not to be involved in their aggregating and nuclear transport of Cx43.Conclusions: 1) AKAP95 and Cx43 bind/aggregate to each other during G1 phase, forming AKAP95-Cx43 complexes/aggregates. After their binding/aggregating, AKAP95 targets nuclear pore and matrix, transporting Cx43 into nucleus. Formed AKAP95-Cx43 complexes/ aggregates do not dissociate in nucleus. The process can be summarized as ‘forming AKAP95-Cx43 complexes/aggregates; transporting Cx43 into nucleus; functioning remaining binding/aggregating’. 2) Cyclin D1 was only found to bind to AKAP95 and Cx43 respectively and function in cytoplasm while cyclin E1 was involved in the binding/aggregation of AKAP95 and Cx43, as well as the nuclear transport of Cx43.

BackgroundAKAP95(A-kinase anchoring protein) and Cx43 (connexin 43) express abnormally in lung cancer cells. As potential tumor therapeutic targets, specific process of bindings and dynamic changes of Cx43-AKAP95 complex in lung cancer cells may guide further treatments and detections of lung cancer. However, the process remains unclear now. We are aiming at investigating the dynamic changes of expression, localization, and binding of AKAP95 and Cx43, as well as their interaction with cyclin D1 and cyclin E1 in lung cancer cells during G1 phase.MethodsA549 and Beas-2B cells were arrested at preliminary stage(P), middle stage(M) and restriction point(R) of G1 phase and Western blot(WB), Confocal laser scanning microscopy (CLSM) and Transmission electron microscope (TEM) were used in our study to detect proteins to provide further evidence of the correlation of these proteins.Results: 1) AKAP95 carries Cx43 into the nucleus through the nuclear pore by binding to it during G1 phase. Some AKAP95 and Cx43 can aggregate and form larger protein aggregates. The process happens mainly during R stage. 2) AKAP95 and Cx43 mainly bind to cyclin D1 during P and M stage while bind to cyclin E1 during R stage respectively. Complexes of AKAP95-cyclin D1 and Cx43-cyclin D1 cannot enter nucleus while AKAP95-cyclin E1 and Cx43-cyclin E1 can.Conclusions1) Binding process of AKAP95-Cx43 complexes/ aggregates can be summarize as ‘bind and aggregate -target and enter nucleus- keep binding/aggregating in nucleus’. 2) Cyclin E1 was involved in the binding/aggregation and nuclear entry of AKAP95 and Cx43 while cyclin D1 only binds to them respectively in the cytoplasm.

Quantum dots (QDs) have numerous potential applications in lighting, engineering, and biomedicine. QDs are mainly excreted through the kidney due to their ultrasmall sizes; thus, the kidneys are target organs of QD toxicity. Here, an organoid screening platform is established and used to study the nephrotoxicity of QDs. Organoids are templated from monodisperse microfluidic Matrigel droplets and found to be homogeneous in both tissue structure and functional recapitulation within a population and suitable for the quantitative screening of toxic doses. Kidney organoids are proved displaying higher sensitivity than 2D-cultured cell lines. Similar to metal-containing QDs, black phosphorus (BP)-QDs are found to have moderate toxicity in the kidney organoids. The nephrotoxicity of BP-QDs are validated in both mice and human renal tubular epithelial cells. BP-QDs are also found to cause insulin insensitivity and endoplasmic reticulum (ER) stress in the kidney. Furthermore, ER stress-related IRE1α signaling is shown to mediate renal toxicity and insulin insensitivity caused by BP-QDs. In summary, this work demonstrates the use of constructed kidney organoids as 3D high-throughput screening tools to assess nanosafety and further illuminates the effects and molecular mechanisms of BP-QD nephrotoxicity. The findings will hopefully enable improvement of the safety of BP-QD applications.

In the present study, we developed a nano-integrated diagnostic and therapeutic platform with oxidation–reduction reactions in tumor microenvironments (TMEs). The proposed platform resolved the contradiction of particle size between the enhanced permeability and retention (EPR) effect and tumor interstitial penetration, as well as poor circulation and low drug-loading efficiency. Flower-like MnO2 NPs were used as the core and modified with hyaluronate (HA) and H2PtCl6 to obtain MnO2–HA@H2PtCl6 (MHP). The maximum drug-loading efficiency rate of H2PtCl6 reached 35% due to its chelation with HA. MHP showed satisfactory integrity and stability during circulation and can also be used as a magnetic resonance imaging (MRI) contrast agent. In addition, MHP as a radiosensitizer achieved an excellent tumor inhibition effect in combination with radiotherapy. Importantly, MHP released ultra-small nanoparticles, USNPs, (∼20 nm) through the supramolecular self-assembly abilities of Mn2+, HA, and H2PtCl6 in TMEs, leading to the increase of penetration into multicellular spheres and solid tumors (Scheme), as well as prolonging its retention in tumors.

As ubiquitous, persistent organic pollutants, polycyclic aromatic hydrocarbons (PAHs) have adverse impacts on human health. Phenanthrene (Phe) is one of the most abundant PAHs in the environment. However, the long-term effects of exposure to environmental level of Phe on the kidneys and the potential mechanisms are unclear. T helper (Th) cells, a subtype of CD4+ T cells that play a central role in the renal immune microenvironment. In this study, male mice were chronically exposed to 5, 50, and 500 ng/kg bw Phe every other day for total 210 days. Those results indicated that environmental Phe exposure caused kidney hypertrophy, injury and fibrosis in the mice. Chronic, long-term environmental level of Phe exposure did not significantly alter the innate immune response but induced adaptive immune response changes (Th1/Th2 related cytokines release), causing a type 1 immune response in the 5 ng/kg bw Phe group and a type 2 immune response in the high dose groups (50 and 500 ng/kg bw). This study provides novel insights into the roles of adaptive immune response in long-term PAH exposure-induced chronic kidney injury and fibrosis, which is beneficial for further understanding the potential health hazards of PAHs and providing new avenues for immune intervention strategies to alleviate PAHs toxicity.

Black phosphorus quantum dots (BP-QDs) are a new type of zero-dimensional (0D) nanomaterial that has been widely used due of their superior properties in many biomedical fields, but limited studies have focused on the biocompatibility of BP-QDs, particularly in the respiratory system. In this study, we investigated the potential lung cell toxicity of BP-QDs in vitro. Two human lung-derived cells, A549 and Beas-2B, were treated with 5∼20 μg/mL BP-QDs for 24 h. The results showed that BP-QDs triggered significant lung cell toxicity, including a dose-dependent decrease in cell viability, lactate dehydrogenase (LDH) leakage, cell shape changes, cellular oxidative stress and cell cycle arrest. In addition, pretreatment with the classical phagocytosis inhibitor cytochalasin D (Cyto D) alleviated the decrease in cell viability and LDH leakage induced by BP-QDs. In contrast, BP-QDs induced the production of cellular reactive oxygen species (ROS) and decreases in the glutathione level, whereas the ROS scavenger N-acetyl-L-cysteine (NAC) could protect A549 and Beas-2B cells from BP-QD-induced cellular oxidative stress. Taken together, the results from this study indicate that the potential toxic effects and mechanisms of BP-QDs in two different human lung cells should be considered to evaluate the lung cell safety of BP-QDs.

Nanosafety is a major concern for nanotechnology development. Evaluation of the transcriptome and the DNA methylome is proposed for nanosafety assessments. RNA m6A modification plays a crucial role in development, disease, and cell fate determination through regulating RNA stability and decay. Here, since black phosphorus quantum dots (BPQDs), among many other types of QDs, increase the global m6A level and decrease the demethylase ALKBH5 level in lung cells, the epitranscriptome is taken into consideration for the first time to evaluate nanosafety. Both the transcriptome and m6A epitranscriptome analyses show that BPQDs alter many biological processes, such as the response to selenium ions and the lipoxygenase pathway, indicating possible ferroptosis activation. The results further show that BPQDs cause lipid peroxidation, mitochondrial dysfunction, and iron overload. Recognition of these modified mRNAs by YTHDF2 leads to mRNAs' decay and eventually ferroptosis. This study shows that RNA m6A modification not only is a more sophisticated indicator for nanosafety assessment but also provides novel insight into the role of RNA m6A in regulating BPQD-induced ferroptosis, which may be broadly applicable to understanding the functions of RNA m6A under stress.

Previous studies have shown the adversely neurodevelopmental effects of exposure to benzo(a)pyrene (BaP) at early life stage. However, it is unclear the effects of lactational exposure to environmentally relevant BaP on anxiety-like behavior and the molecular mechanisms related. In this study, lactational exposure to 1 and 10 μg/kg bw BaP from postnatal day 3–21 caused anxiety-like behavior and alterations of the expressions of the neurodevelopment and anxiety-related genes in adolescence male mice using O cycle maze. Moreover, BaP exposure increased the expression level of glial fibrillary acidic protein, a typical marker of astrocytes, in hippocampus of male offspring. The release of pro-inflammatory cytokines interleukin 6 and tumor necrosis factor α was also elevated in BaP-treated offspring. Further, lactational exposure to BaP decreased the level of glutathione and the expressions of antioxidant genes (Thioredoxin 1 and Glutaredoxin 2) in male offspring. Our study demonstrated that environmentally relevant BaP lactational exposure caused anxiety-like behavior in male offspring involved in astrocytic activation, neuroinflammation, and antioxidant capability dysfunction.