Toxicology and applied pharmacology最新文献

Cadmium (Cd²⁺) is a heavy metal that is a major hazardous environmental contaminant, ubiquitously present in the environment. Cd²⁺ exposure has been closely associated with an increased prevalence and severity of neurological and cardiovascular diseases (CVD). The blood-brain barrier (BBB) plays a crucial role in protecting the brain from external environmental factors. Mitochondria play an important role in maintaining the barrier function of brain endothelial cells by regulating energy metabolism and redox homeostasis. In this study, we aimed to assess the cytotoxic effects of Cd²⁺ on the integrity and function of brain endothelial cells. After 24 h of exposure, Cd²⁺ reduced cell survival, tight junction protein expression, and trans-endothelial electrical resistance (TEER) in bEnd.3 cells suggest a potential BBB integrity disruption by Cd²⁺ exposure. To clarify the underlying mechanism, we further investigated the role of mitochondria in iron overload-mediated cell death following Cd²⁺ exposure. Cd²⁺ induced a substantial reduction in mitochondrial basal respiration and ATP production in brain endothelial cells, suggesting mitochondrial dysfunction. In addition, Cd²⁺ exposure led to impaired autophagy, elevated iron levels, and increased lipid peroxidation, indicating the initiation of ferroptosis, a form of cell death triggered by iron. In summary, our research suggests that Cd²⁺ exposure can disrupt BBB function by causing mitochondrial dysfunction and disrupting iron homeostasis.

Modeling brain development and function is challenging due to complexity of the organ. Human pluripotent stem cell (PSC)-derived brain-like organoids provide new tools to study the human brain. Compared with traditional in vivo toxicological studies, these 3D models, together with 2D cellular assays, enhance our understanding of the mechanisms of developmental neurotoxicity (DNT) during the early stages of neurogenesis and offer numerous advantages including a rapid, cost-effective approach for understanding compound mechanisms and assessing chemical safety. Arsenic (As) exposure is associated with DNT, although the mechanisms involved are not well-defined. Here, we used 3D PSC-derived embryoid bodies (EBs) to recapitulate events involved in embryogenesis and neurogenesis before neural induction, and EB-derived cerebral organoids to mimic neural development in vivo. As (0.5 μM; 35 ppb) increased ectoderm differentiation within the EBs by upregulating genes (PAX6, SOX1) critical for embryonic development. Histological staining of EBs showed As disrupted neural rosette structures. qPCR and RNA-seq showed As inhibited expression of markers of mature neural cells (MAP2+/vGLUT2+) and astrocytes (GFAP+). In organoids, Ingenuity Pathway Analysis was used to identify the top 5 pathways affected by As exposure, and Gene Ontology enrichment analysis found several key signaling pathways to be inhibited by As exposure. These data provide insights into pathways contributing to As-induced inhibition of neurite outgrowth and disrupted neural rosette structures in the 2D neurite outgrowth assay and in organoids, respectively. Results herein show this multipronged 2D/3D approach can provide valuable insights into cellular events and molecular mechanisms of As-induced DNT.

The widespread use of polyethylene terephthalate (PET) in food and beverage packaging raises concerns about its potential health effects, particularly when PET-derived nanoplastics (PET-NPs) are released into the environment. This study investigates the reproductive toxicity of PET-NPs in male mice. Mice were exposed to PET-NPs at doses of 0.1 mg/day and 0.5 mg/day for 28 days, and the testes index, sperm count, sperm morphology, Reactive Oxygen Species (ROS) production, DNA integrity, histopathology, and spermatogenesis were evaluated. PET-NP exposure resulted in a significant decrease in sperm concentration and an increase in abnormal spermatozoa-particularly blunt-headed sperm and sperm with neck and tail anomalies- and elevated ROS levels in testicular tissue in a dose-dependent manner (p < 0.05). Additionally, PET-NPs induced DNA strand breaks, as demonstrated by the COMET assay (p < 0.05). Histopathological analysis revealed disorganization of the germinal epithelium, vacuolization, reduced sperm density, and increased interstitial spaces, accompanied by a significant decline in spermatogenic activity, as assessed by Johnsen scoring. These findings strongly suggest that the observed adverse effects on male reproductive health, including sperm abnormalities, DNA damage, and impaired spermatogenesis, are primarily driven by ROS-induced oxidative stress. The observed changes provide clear evidence of the adverse effects of subchronic exposure to PET nanoplastics on male reproductive health, highlighting the inherent risks associated with nanoplastic exposure and offering crucial insights for public health awareness and regulatory considerations.

Cisplatin is a widely used chemotherapeutic agent, but its clinical utility is limited by side effects affecting different systems and organs, including hepatotoxicity in some cases. Baicalin, a flavonoid isolated from Scutellaria baicalensis, possesses antioxidant, anti-inflammatory and hepatoprotective properties, but its low bioavailability limits its therapeutic use. This study aimed to investigate whether a nanoemulsion formulation of baicalin could enhance its efficacy against cisplatin-induced hepatic injury in rats. Rats were orally treated daily with baicalin either in nanoformulation (10 or 20 mg/kg body weight per day) or conventional form (100 mg/kg body weight per day) for 12 days. Cisplatin (10 mg/kg body weight) was injected intraperitoneally on day six and day twelve to induce hepatic injury. Samples were collected on day thirteen. Serum markers, oxidative stress parameters, inflammatory markers, cellular energy status, histopathology, and other endpoints were evaluated. Results revealed that cisplatin caused elevated serum enzymes, oxidative stress, inflammation, DNA damage, depleted cellular energy levels, and induced severe hepatic histological changes. The baicalin nanoemulsion especially the higher 20 mg/kg dose, significantly ameliorated cisplatin-induced abnormalities across the various parameters. The conventional baicalin suspension also provided protection, albeit to a lesser degree than the nanoemulsion. In conclusion, administering baicalin as a nanoemulsion potentiated its hepatoprotective effects against cisplatin toxicity. The nanoemulsion formulation strategy was proven promising for enhancing baicalin's therapeutic utility.

The incidence rate and mortality rate of breast cancer remain high, and there is an urgent need for safe and effective drugs. The excellent biological activity of hesperidin (HE) is a potential drug for the treatment of breast cancer. In this study, silk fibroin peptides (SFP) were used as delivery carriers and HE loaded SFP nanofibers (SFP/HE NFs) was prepared. The in vitro results showed that SFP/HE NFs significantly inhibited the proliferation and migration of breast cancer cell MDA-MB-231 compared with free HE. The mechanism results demonstrated that SFP/HE NFs induced apoptosis and DNA double stranded damage (DSBs) and further activated the cyclic monophosphate guanosine adenosine monophosphate synthase- stimulator of interferon gene (cGAS-STING) pathway. The in vivo studies showed that SFP/HE NFs treatment significantly inhibited the growth of breast cancer, with an inhibition rate of 65.9 % (100 mg/kg). In vivo mechanism studies also demonstrated that the anti-tumor activity of SFP/HE NFs was related to the activation of the cGAS-STING pathway. Interestingly, we found that the combination of SFP/HE NFs and cisplatin not only enhanced the anti-tumor activity of cisplatin, but also alleviated cisplatin induced nephrotoxicity. In conclusion, our results demonstrate the benefits of activating the cGAS-STING pathway in the treatment of breast cancer, which is expected to provide potential candidates for combined treatment of breast cancer.

T-2 toxin, a prevalent mycotoxin, represents a notable global public health risk. Neutrophil extracellular traps (NETs) and ferroptosis are involved in a variety of pathophysiological processes and are implicated in goat immunity. However, the impact of T-2 toxin on NETs release, ferroptosis, and their interplay have not been previously documented. In this study, neutrophils were stimulated with T-2 toxin for 4 h. The structure and mechanism of NETs were analyzed using immunofluorescence and Pico Green staining. The expressions of glutathione peroxidase 4 (GPX4) and ferritin (FT) was quantified by qRT-PCR and western blotting. The levels of ROS and lipid ROS were assessed using DCFH-DA and C11 BODIPY 581/591 probes, and cellular mitochondria Fe²⁺ were detected by using Mito-FerroGreen probe. Inhibitors were utilized to explore the interaction between these two processes. The results confirmed that the T-2 toxin stimulated the NETs production, characterized by a structure co-modified by citrullinated histones (citH3), neutrophil elastase (NE) and DNA. Notably, significant inhibition of NETs production by T-2 toxin was observed with the NOX inhibitor DPI (P < 0.001), the ERK inhibitor U0126 (P < 0.001), the TLR2 inhibitor C29 (P < 0.001), and the TLR4 inhibitor TLR4-IN-C34 (P < 0.001). T-2 toxin triggered ferroptosis in neutrophils by suppressing GPX4 and FT expression, elevating ROS and lipid ROS, and augmenting the concentration of mitochondrial Fe²⁺. The ferroptosis inhibitor Fer-1 could rescue this induction; however, Fer-1 was unable to inhibit NETs which is induced by T-2 toxin. Conversely, T-2 toxin effectively triggered the downregulation of GPX4, which was counteracted by DPI, U0126, C29, and C34. This research elucidates the immunotoxic mechanisms of T-2 toxin in goat neutrophils and offers a novel perspective on preventing and treating T-2 toxin.

One of the potential risk factors of recombinant adeno-associated virus (rAAV)-based gene therapy is insertional mutagenesis, which has been associated with the development of hepatocellular carcinoma (HCC) in rAAV-treated neonatal mice. The objective of this study was to investigate if well-established in vitro cell transformation assays (CTA) in mouse cell lines can detect AAV2 or AAVdj-mediated cell transformation. Since AAV integration at the Rian locus in neonatal mice has been implicated in AAV-mediated HCC, an rAAV vector specifically targeting the mouse Rian locus and an additional rAAV vector previously shown to cause HCC in neonatal mice were both tested for the induction of cell transformation in NIH3T3 cells. To increase the frequency of AAV DNA integration at the Rian locus in the genome of NIH3T3 cells, double-strand breaks in Rian locus of NIH3T3 cells were created by CRISPR-Cas9 to increase the homologous crossover between viral DNA and the cell genome. When transduced cells were assayed in CTA, the transformation frequency observed in AAV-transduced NIH3T3 cells was not significantly different from that of untreated vehicle cells. The finding that rAAV is unable to transform the NIH3T3 in vitro indicates that either the transformation rate is less than the spontaneous rate of NIH3T3 cellular transformation, or in vitro CTA are not predictive of rAAV-induced HCC in mice.

Bisphenol A (BPA), an endocrine disruptor, is linked to cancer progression in estrogen-responsive tissues, but its role in promoting colorectal cancer (CRC) progression in the context of obesity remains underexplored. This study examines BPA's influence on CRC in obese Sprague-Dawley rats using network toxicology and experimental models. Computational analysis using the Database for Annotation, Visualization, and Integrated Discovery identified pathways such as "CRC" and "chemical carcinogenesis-receptor activation", implicating the PI3K-AKT pathway in IL-1 beta upregulation and BPA's role in CRC during obesity. Thirty male rats were grouped (n = 6) as follows: N (normal diet), NC (normal diet + CRC), HC (high-fat diet + CRC), NCB (normal diet + CRC + BPA), and HCB (high-fat diet + CRC + BPA). CRC was induced with 1,2-dimethylhydrazine (40 mg/kg), and BPA (25 mg/kg) was administered for 19 weeks. Although BPA exposure did not affect body weight or biochemical parameters, the HCB group exhibited significant histopathological changes in the colon, including lymphoid hyperplasia, liver damage, and increased IL-1β levels. Furthermore, diet influenced adipocyte size, exacerbating BPA's effects on CRC progression. Findings suggest BPA may worsen CRC progression in obese rats through identified pathways, promoting multi-organ pathology and underscoring the need for stricter regulations, especially for vulnerable populations. ENVIRONMENTAL IMPLICATION: Bisphenol A (BPA), a widespread environmental contaminant, is increasingly linked to serious health issues, including cancer, in susceptible populations. Our study highlights BPA's role in promoting obesity-driven colorectal cancer (CRC) progression, demonstrating its carcinogenic potential in high-risk contexts. These findings emphasize the urgent need for regulatory scrutiny of BPA exposure, particularly in obese individuals, and support the development of safer alternatives. Addressing BPA's impact can contribute to preventive health strategies and inform policies aimed at reducing environmental and public health risks associated with endocrine-disrupting chemicals.

This study explored the vasodilatory mechanisms of the sodium-glucose cotransporter-2 inhibitor remogliflozin using femoral arteries of rabbits. Remogliflozin dilated femoral arterial rings pre-contracted with phenylephrine in a concentration-dependent manner. Pretreatment with the Ca²⁺-sensitive K⁺ channel inhibitor (paxilline), the ATP-sensitive K⁺ channel inhibitor (glibenclamide), or the inwardly rectifying K⁺ channel inhibitor (Ba²⁺) did not alter the vasodilatory effect. However, vasodilation was significantly reduced by pretreatment with the voltage-dependent K⁺ (Kv) channel inhibitor (4-AP) and with the Kv1.5 subtype inhibitor (DPO-1) but not with Kv2.1 or Kv7 subtype inhibitor. Neither endothelium removal nor the inhibition of nitric oxide production altered the vasodilatory effect of remogliflozin. However, pretreatment with the sarcoplasmic/endoplasmic reticulum Ca²⁺-ATPase (SERCA) pump inhibitors thapsigargin and cyclopiazonic acid effectively reduced the remogliflozin effect, as did pretreatment with cGMP/PKG-related but not cAMP/PKA-related signaling pathway inhibitors. These results indicate that remogliflozin-mediated dilation of the femoral artery occurs via the activation of Kv channels, mainly the Kv1.5 subtype, SERCA pump, and cGMP/PKG-related signaling pathways.

Background: Lung cancer is a medical ailment with high mortality and prevalence rates. Artemisinin (ART) and its derivatives exhibit anti-cancer properties against various malignancies, including lung cancer. However, further research is required to determine the precise anti-cancer mechanisms of ART. Hence, this study aimed to utilize network pharmacology to preliminarily investigate the therapeutic effectiveness and mode of action of this medication.

Methods: Using a bioinformatics approach, five target proteins with the strongest connections were selected for docking. Gene enrichment analysis was performed, and the ART target proteins were predicted. Various methods, including methyl thiazolyl tetrazolium (MTT) assays, colony formation assays, microsphere formation assays, flow cytometry, and western blotting analysis, were employed to assess the impact of ART on the malignant characteristics of lung cancer cells.

Results: Bioinformatic analysis identified 51 ART target genes in lung adenocarcinoma for further analysis. Pathway enrichment analysis of target genes revealed 639 enriched Gene Ontology-Biological Process (GO BP) and 17 enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. These findings imply that ART may control the IL-6 signaling pathway by focusing on important molecules such as CDK4 and IL-6. The ART-treated group experienced apoptosis induction, cell cycle arrest, and inhibition of cell proliferation and microsphere formation compared with the control group (p < 0.05, p < 0.01). Additionally, ART reduced the protein expression of CDK4, COX2, ERBB2, CD44, and EpCAM while increasing that of caspase 3, IL-6, p53, and SRC (p < 0.01).

Conclusion: ART inhibited the growth and stemness of HCC827 cells.