Topically applied fullerenols protect against radiation dermatitis by scavenging reactive oxygen species.

Adverse skin reactions caused by ionizing radiation are collectively called radiation dermatitis (RD), and the use of nanomedicine is an attractive approach to this condition. Therefore, we designed and large-scale synthesized fullerenols that showed free radical scavenging ability in vitro. Next, we pretreated X-ray-exposed cells with fullerenols. The results showed that pretreatment with fullerenols significantly scavenged intracellular reactive oxygen species (ROS) produced and enhanced the antioxidant capacity, protecting skin cells from X-ray-induced DNA damage and apoptosis. Moreover, we induced RD in mice by applying 30 Gy of X-ray irradiation, followed by treatment with fullerenols. We found that after treatment, the RD scores dropped, and the histological results systematically demonstrated that topically applied fullerenols could reduce radiation-induced skin epidermal thickening, collagen deposition and skin appendage damage and promote hair regeneration after 35 days. Compared with Trolamine cream, a typical RD drug, fullerenols showed superior radiation protection. Overall, the in vitro and in vivo experiments proved that fullerenols agents against RD.

Estradiol protects female mice from hyperuricemia induced by PCB138 exposure.

Polychlorinated biphenyls (PCBs) are a type of persistent organic pollutant (POP). Our previous study demonstrated that exposure to 0.5-50 µg/kg bw PCB138 during postnatal days (PND) 3-21 led to elevated serum uric acid (UA) levels and kidney injury in adult male mice. Given that the prevalence of hyperuricemia (HUA) is significantly lower in women than in men, it is worth investigating whether POP-induced HUA and its secondary kidney injury have sexual dimorphism. Herein, we exposed female mice to 0.5-50 µg/kg bw PCB138 during PND 3-21, resulting in elevated serum UA levels, but without causing significant kidney damage. Concurrently, we found a negative correlation between serum 17ß-estradiol (E2) and serum UA levels. We also observed down-regulation of estrogen receptor (ER) protein levels in the kidneys of the PCB138-exposed groups. Furthermore, our study showed that E2 rescued the increased UA level and cytotoxicity caused by HUA in human renal tubular epithelial (HK-2) cells. Collectively, our findings suggest that E2 likely plays a crucial protective role in PCB138-induced HUA and kidney injury in female mice. Our research highlights the existence of sexual dimorphism in kidney injury secondary to HUA induced by POPs, which could provide guidance for individuals of different genders in preventing kidney injury caused by environmental factors.

The hepatoprotective effects of Herbt Tea Essences on phenanthrene-induced liver damage in mice.

Phenanthrene (Phe), one of the most frequently occurring pollutants in nature, can cause substantial damage to the human liver. Herbt Tea Essences (HTE), a kind of black tea extract with strong anti-inflammatory activity, can protect humans against disease. Currently, whether HTE can protect the liver from Phe-induced hepatotoxicity remains unclear. Herein, we explore the protective effects of HTE against Phe-induced hepatotoxicity. Our results showed that Phe exposure could significantly induce liver damage and increase serum hepatic enzyme levels in mice. HTE could prevent liver damage and recover the expression levels of inflammatory factors. Furthermore, we found that HTE suppressed the excessive activation of the nuclear transcription factor kappa-B and transforming growth factor-ß/SMAD signaling pathways to alleviate Phe-induced liver inflammation and fibrosis. Overall, our data showed that HTE treatment could be a new preventive means for Phe-induced liver disease.

Black phosphorus quantum dots cause glucose metabolism disorder and insulin resistance in mice.

Black phosphorus quantum dots (BPQDs) are considered to have wide application prospects due to their excellent properties. However, there is no study on the effect of BPQDs on glucose metabolism. In this study, blood glucose was significantly increased when mice were continuously intragastrically administered 0.1 and 1 mg/kg bw BPQDs. The blood glucose level of the mice was elevated from Day 7 to Day 28. BPQD exposure also decreased the area under the curve (AUC) of the oral glucose tolerance test (OGTT). After exposure, the pancreas somatic index was increased. Moreover, the serum insulin and glucagon levels were elevated and the relative area of islet ß cells was increased in BPQD-exposed mice, while insulin signaling cascades were reduced in muscle tissues. In summary, our study demonstrated for the first time that BPQD exposure induces glucose disorder and insulin resistance in muscle, which is helpful to understand the biosafety of black phosphorus nanomaterials and promote the sustainable development of nanotechnology.

Role of RNA m6A modification in titanium dioxide nanoparticle-induced acute pulmonary injury: An in vitro and in vivo study.

RNA N6-methyladenosine (m6A) modification regulates the cell stress response and homeostasis, but whether titanium dioxide nanoparticle (nTiO2)-induced acute pulmonary injury is associated with the m6A epitranscriptome and the underlying mechanisms remain unclear. Here, the potential association between m6A modification and the bioeffects of several engineered nanoparticles (nTiO2, nAg, nZnO, nFe2O3, and nCuO) were verified thorough in vitro experiments. nFe2O3, nZnO, and nTiO2 exposure significantly increased the global m6A level in A549 cells. Our study further revealed that nTiO2 can induce m6A-mediated acute pulmonary injury. Mechanistically, nTiO2 exposure promoted methyltransferase-like 3 (METTL3)-mediated m6A signal activation and thus mediated the inflammatory response and IL-8 release through the degeneration of anti-Mullerian hormone (AMH) and Mucin5B (MUC5B) mRNAs in a YTH m6A RNA-binding protein 2 (YTHDF2)-dependent manner. Moreover, nTiO2 exposure stabilized METTL3 protein by the lipid reactive oxygen species (ROS)-activated ERK1/2 pathway. The scavenging of ROS with ferrostatin-1 (Fer-1) alleviates the ERK1/2 activation, m6A upregulation, and the inflammatory response caused by nTiO2 both in vitro and in vivo. In conclusion, our study demonstrates that m6A is a potential intervention target for alleviating the adverse effects of nTiO2-induced acute pulmonary injury in vitro and in vivo, which has far-reaching implications for protecting human health and improving the sustainability of nanotechnology.

Arsenic induces bronchial epithelial carcinogenesis with mitochondrial dysfunction through AKAP95-mediated cell cycle alterations.

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 (NaAsO2) for the short-term or treated with low dose for long-term. The data showed that both short- and long-term treatment promoted G1/S transition of Beas-2B cells, inducing a significant increase in the expression of AKAP95, cyclin D1, cyclin D2, and cyclin E1. However, silencing AKAP95 by treating cells with siAKAP95 exerted a protective function that inhibited G1/S transition, suggesting a regulatory mechanism of AKAP95 on the cell cycle during cell malignant transformation induced by NaAsO2. In addition, mitochondrial dysfunctions occurred during NaAsO2 exposure. Beas-2B cells exposed to low-dose NaAsO2 for long-term were subcultured for 20 generations, and the exposure time was positively proportional to the growth and migration rate of the cells. The exposed cells were used in a tumor-bearing transplantation experiment (mice), and the results showed that the longer the exposure time, the faster the tumor volume growth rate of As-Beas-2B cells. Tumor tissues were excised for hematoxylin-eosin staining, which showed altered cell morphology and increased volume.

Nanoparticle-Induced m6A RNA Modification: Detection Methods, Mechanisms and Applications.

With the increasing application of nanoparticles (NPs) in medical and consumer applications, it is necessary to ensure their safety. As m6A (N6-methyladenosine) RNA modification is one of the most prevalent RNA modifications involved in many diseases and essential biological processes, the relationship between nanoparticles and m6A RNA modification for the modulation of these events has attracted substantial research interest. However, there is limited knowledge regarding the relationship between nanoparticles and m6A RNA modification, but evidence is beginning to emerge. Therefore, a summary of these aspects from current research on nanoparticle-induced m6A RNA modification is timely and significant. In this review, we highlight the roles of m6A RNA modification in the bioimpacts of nanoparticles and thus elaborate on the mechanisms of nanoparticle-induced m6A RNA modification. We also summarize the dynamic regulation and biofunctions of m6A RNA modification. Moreover, we emphasize recent advances in the application perspective of nanoparticle-induced m6A RNA modification in medication and toxicity of nanoparticles to provide a potential method to facilitate the design of nanoparticles by deliberately tuning m6A RNA modification.

Early life PCB138 exposure induces kidney injury secondary to hyperuricemia in male mice.

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.

RNA m6A Modification Alteration by Black Phosphorus Quantum Dots Regulates Cell Ferroptosis: Implications for Nanotoxicological Assessment.

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.

Acute and subacute oral toxicity of propylene glycol enantiomers in mice and the underlying nephrotoxic mechanism.

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 1ß, 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.

Long-term exposure to environmental level of phenanthrene causes adaptive immune response and fibrosis in mouse kidneys.

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.

Cytotoxicity of black phosphorus quantum dots on lung-derived cells and the underlying mechanisms.

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.

Black Phosphorus Quantum Dots Cause Nephrotoxicity in Organoids, Mice, and Human Cells.

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.

A nano-integrated diagnostic and therapeutic platform with oxidation-reduction reactions in tumor microenvironments.

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.

Lactational exposure to environmentally relevant benzo(a)pyrene causes astrocytic activation and anxiety-like behavior in male mice.

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.

High-content analysis for mitophagy response to nanoparticles: A potential sensitive biomarker for nanosafety assessment.

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.