Assessment of Thyroid Endocrine Disruption Effects of Parabens Using In Vivo, In Vitro, and In Silico Approaches.

The extensive applications of parabens in foods, drugs, and cosmetics cause inevitable exposure to humans. Revealing the developmental toxicity of parabens is of utmost importance regarding their safety evaluation. In this study, the effects of four commonly used parabens, including methyl paraben (20 ∼ 200 µM), ethyl paraben (20 ∼ 100 µM), propyl paraben (5 ∼ 20 µM), and butyl paraben (BuP, 2 ∼ 10 µM), were investigated on the early development of zebrafish embryos and larvae. The underlying mechanisms were explored from the aspect of their disturbance in the thyroid endocrine system using in vivo, in vitro, and in silico assays. Paraben exposure caused deleterious effects on the early development of zebrafish, with BuP displaying the highest toxicity among all, resulting in the exposure concentration-related mortality, decreased hatching rate, reduced body length, lowered heart rate, and the incidence of malformation. Further investigation showed that paraben exposure reduced thyroid hormone levels and disturbed the transcriptional expressions of the target genes in the hypothalamic-pituitary-thyroid axis. Molecular docking analysis combined with in vitro GH3 cell proliferation assay testified that all test parabens exhibited thyroid receptor agonistic activities. The findings confirmed the developmental toxicity of the test parabens and their thyroid endocrine disruption effects, providing substantial evidence on the safety control of paraben-based preservatives.

Assessment of antiviral activity and mechanism of rhein on newcastle disease virus (La Sota strain IV) in vitro.

Current research is focused on the development of drug candidates from natural products. Rhein a Traditional Chinese Medicine (TCM) from Polygonaceae (rhubarb) has exhibited antioxidant, anti-inflammatory and anticancer activities, however no work has reported its antiviral potential, thus this study was performed to investigate the antiviral activities of rhein on new castle disease virus (NDV) in vitro.NDV infection of chicken embryo fibroblasts (CEFs) was prepared using 10-day-old specific pathogen free chicken embryos. Cytotoxicity and anti-viral activities of rhein were assessed using the MTT method. The interaction between NDV and cell membrane proteins were also detected using virus overlay protein binding assay (VOPBA). In addition NDV genes expressions in CEFs were measured using real-time fluorescent quantitative (RTFQ) PCR.The results showed that rhein effectively inhibit NDV activities maximal safe concentration of 0.125 mg/ml. This finding indicated that, rhein could be used as future antiviral drug against NDV.[Formula: see text].

Assessment of the pulmonary adaptive immune response to Cladosporium cladosporioides infection using an experimental mouse model.

Cladosporium cladosporioides causes asthma and superficial and deep infections, mostly in immunodeficient individuals and animals. This study aimed to investigate whether C. cladosporioides spores can enter the lungs through pulmonary circulation and influence pulmonary immune response. We intravenously injected mice with C. cladosporioides spore suspension and conducted several assays on the lungs. Pulmonary hemorrhage symptoms and congestion were most severe on days 1, 2, and 3 post-inoculation (PI). Extensive inflammatory cell infiltration occurred throughout the period of infection. More spores and hyphae colonizing the lungs were detected on days 1, 2, and 3 PI, and fewer spores and hyphae were observed within 21 d of infection. Numerous macrophages, dendritic cells, and neutrophils were observed on day 5 PI, along with upregulation of CD54, an intercellular adhesion molecule. Th1 and Th2 cells increased after infection; specifically, Th2 cells increased considerably on day 5 PI. These results suggest that days 2 and 5 PI represent the inflammatory peak in the lungs and that the Th2 and Th1 signaling pathways are potentially involved in pulmonary immune responses. In conclusion, the further adaptive immune responses played important roles in establishing effective pulmonary immunity against C. cladosporioides systemic infections based on innate immune responses.