Environmental Toxicology最新文献

Inflammation is an intrinsic protective mechanism against various forms of cellular injuries in humans; however, its undesired activation results in tissue damage and cell death. The onset of chronic inflammation and oxidative stress are the key characteristics of autoimmune inflammatory diseases such as rheumatoid arthritis (RA), for which an effective treatment is yet to be developed. Therefore, in this study, we investigated the protective effects and molecular mechanisms of a novel herbal preparation, Jing-Si herbal tea (JS), against H₂O₂-induced inflammation and cellular damage in HIG-82 synoviocytes. We found that JS did not show any significant alterations in cell viability at <188 μg/mL; however, a cytotoxic effect was observed at 188-1883 μg/mL concentrations tested. We found that expressions of inflammation associated extracellular matrix (ECM)-degrading proteases MMP-13, ADAMTS-2, -8, and -17 were abnormally enhanced under H₂O₂-induced pathological oxidative stress (ROS) in HIG-82 cells. Interestingly, JS treatment not only reduced the ROS levels but also significantly repressed the protein expressions of collagen degrading proteases in a dose-dependent manner. Treatment with JS showed enhanced cell viability against H₂O₂-induced toxic ROS levels. The expressions of cell protective aggrecan, Collagen II, and Bcl-2 were increased, whereas MMP-13, ADAMTS-2, Cytochrome C, and cleaved Caspase 3 were decreased by JS under inflammatory agents H₂O₂, MIA, LPS, and TNF-α treatment, respectively, in HIG-82 cells. Interestingly, the cytoprotective effect of JS treatment was attributed to a decreased mitochondrial localization of Bax and a reduction of Cytochrome C release into the cytoplasm of H₂O₂-treated HIG-82 cells. Collectively, our results suggest a novel protective mechanism of JS for RA treatment, which could be potentially applied as a complementary treatment or as an alternative therapeutic approach to mitigate inflammatory diseases.

Clear cell renal cell carcinoma (ccRCC) is characterized by its aggressive behavior and complex molecular heterogeneity, posing significant challenges for treatment and prognostication. This study offers a comprehensive analysis of ccRCC by leveraging both bulk and single-cell RNA sequencing data, with a specific aim to unravel the complexities of sphingolipid metabolism and the intricate dynamics within the tumor microenvironment (TME). By examining ccRCC samples sourced from public databases, our investigation delves deep into the genetic and transcriptomic landscape of this cancer type. Employing advanced analytical techniques, we have identified pivotal patterns in gene expression and cellular heterogeneity, with a special focus on the roles and interactions of various immune cells within the TME. Significantly, our research has unearthed insights into the dynamics of sphingolipid metabolism in ccRCC, shedding light on its potential implications for tumor progression and strategies for immune evasion. A novel aspect of this study is the development of a risk score model designed to enhance prognostic predictions for ccRCC patients, which is currently pending external validation to ascertain its clinical utility. Despite its contributions, the study is mindful of its limitations, including a reliance on observational data from public sources and a primary focus on RNA sequencing data, which may constrain the depth and generalizability of the findings. The study does not encompass critical aspects, such as protein expression, posttranslational modifications, and comprehensive metabolic profiles. Moreover, its retrospective design underscores the necessity for future prospective studies to solidify these preliminary conclusions. Our findings illuminate the intricate interplay between genetic alterations, sphingolipid metabolism, and immune responses in ccRCC. This research not only enhances our understanding of the molecular foundations of ccRCC but also paves the way for the development of targeted therapies and personalized treatment modalities. The study underlines the importance of cautious interpretation of results and champions ongoing research using diverse methodologies to thoroughly comprehend and effectively combat this formidable cancer type.

T-2 toxin is a trichothecene mycotoxin and is considered as an extremely inevitable pollutant with potent hepatotoxicity. However, the approach to alleviation of T-2 toxin-triggered hepatotoxicity has been recognized as a serious challenge. Resveratrol (Res) is a polyphenol natural product isolated from various plant species, but its protective effect against T-2 toxin hepatotoxicity and detailed mechanism remains obscure. In the present study, the effect of Res against the hepatotoxicity was evaluated, and the underlying mechanisms were further revealed in mice. Functionally, Res inhibited liver injury, oxidative damage, and mitochondrial dysfunction induced by T-2 toxin. Mechanistically, Res modulated Nrf2-mediated antioxidant pathway and glutathione synthesis inhibition. Collectively, our findings first showed beyond doubt that Res ameliorated T-2 toxin-triggered liver injury by regulating Nrf2 pathways in mice.

Chloroform is a prevalent toxic environmental pollutant in urban settings, posing risks to human health through exposure via various mediums such as air and tap water. The gut microbiota plays a pivotal role in maintaining host health. However, there is a paucity of research elucidating the impact of chloroform exposure on the gut microbiota. In this investigation, 18 SPF Kunming female mice were stratified into three groups (n = 6) and subjected to oral gavage with chloroform doses equivalent to 0, 50, and 150 mg/kg of body weight over 30 days. Our findings demonstrate that subchronic chloroform exposure significantly perturbs hematological parameters in mice and induces histopathological alterations in cecal tissues, consequently engendering marked disparities in the functional composition of cecal microbiota and metabolic equilibrium of cecal contents. Ultimately, our investigation revealed a statistically robust correlation, exhibiting a high degree of significance, between the intestinal microbiome composition and the metabolites that were differentially expressed consequent to chloroform exposure.

Inflammatory cell infiltration is a characteristic feature of COPD and correlates directly with the severity of the disease. Interleukin-23 (IL-23) is a pro-inflammatory cytokine that regulates Th-17 inflammation, which mediates many pathophysiological events in COPD. The primary goal of this study was to determine the role of IL-23 as a mediator of key pathologic processes in cigarette smoke-induced COPD. In this study, we report an increase in IL23 gene expression in the lung biopsies of COPD patients compared to controls and identified a positive correlation between IL23 gene expression and disease severity. In a cigarette smoke-induced murine emphysema model, the suppression of IL-23 with a monoclonal blocking antibody reduced the severity of cigarette smoke-induced murine emphysema. Mechanistically, the suppression of IL-23 was associated with a reduction in immune cell infiltration, oxidative stress injury, and apoptosis, suggesting a role for IL-23 as an essential immune mediator of the inflammatory processes in the pathogenesis of CS-induced emphysema.

World Health Organization data indicate a continuous increase in melanoma incidence, with metastatic melanoma characterized by poor prognosis and drug resistance. The exploration of therapeutics derived from natural products remains an active area of in vitro research. The aim of this study was to determine the antitumor effects of picrasidine I, a natural compound extracted from Picrasma quassioides, against two melanoma cell lines. We selected two metastatic melanoma cell lines, HMY-1 and A2058, for molecular studies, including Western blotting, 4',6-diamidino-2-phenylindole staining, and flow cytometry. Picrasidine I demonstrated cytotoxic effects against the HMY-1 and A2058 melanoma cell lines. It induced cell cycle arrest in the sub-G1 phase and downregulated cell cycle-related proteins (e.g., cyclin A2, D1, cyclin-dependent kinases 4, and 6). In the intrinsic apoptosis pathway, picrasidine I activated proapoptotic proteins (e.g., Bax, Bak, t-Bid, BimL/S) and suppressed the expression of antiapoptotic proteins (e.g., Bcl-2, Bcl-xL), with an observed increase in the quantity of depolarized cells. In addition, the apoptotic effects of picrasidine I were linked to the activation of the c-Jun N-terminal kinase and extracellular signal-regulated kinase pathways and the inhibition of the protein kinase B signaling pathway. A human apoptosis array indicated claspin inhibition upon picrasidine I treatment, suggesting the potential involvement of picrasidine I in apoptosis and cell cycle regulation. Our findings suggest that picrasidine I has potential as a candidate for treating advanced melanoma, and thus these findings warrant further investigation. The modulation of claspin expression by picrasidine I could be investigated further as a potential biomarker to predict its efficacy in related to advanced stages of melanoma.

Subways are widely used in major cities around the world, and subway fine particulate matter (PM_2.5) is the main source of daily PM_2.5 exposure for urban residents. Exposure to subway PM_2.5 leads to acute inflammatory damage in humans, which has been confirmed in mouse in vivo studies. However, the concrete mechanism by which subway PM_2.5 causes airway damage remains obscure. In this study, we found that subway PM_2.5 triggered release of pro-inflammatory cytokines such as interleukin 17E, tumor necrosis factor α, transforming growth factor β, and thymic stromal lymphopoietin from human bronchial epithelial cells (BEAS-2B) in a dose-effect relationship. Subsequently, supernatant recovered from the subway PM_2.5 group significantly increased expression of the aforementioned cytokines in BEAS-2B cells compared with the subway PM_2.5 group. Additionally, tight junctions (TJs) of BEAS-2B cells including zonula occludens-1, E-cadherin, and occludin were decreased by subway PM_2.5 in a dose-dependent manner. Moreover, supernatant recovered from the subway PM_2.5 group markedly decreased the expression of these TJs compared with the control group. Furthermore, inhibitors of toll-like receptors (TLRs) and nuclear factor-kappa B (NF-κB), as well as chelate resins (e.g., chelex) and deferoxamine, remarkably ameliorated the observed changes of cytokines and TJs caused by subway PM_2.5 in BEAS-2B cells. Therefore, these results suggest that subway PM_2.5 induced a decline of TJs after an initial ascent of cytokine expression, and subway PM_2.5 altered expression of both cytokines and TJs by activating TLRs/NF-κB-dependent pathway in BEAS-2B cells. The metal components of subway PM_2.5 may contribute to the airway epithelial injury.