Role of the PARP1/NF-κB Pathway in DNA Damage and Apoptosis of TK6 Cells Induced by Hydroquinone.

Hydroquinone(HQ) is a widely used industrial raw material and is a topical lightening product found in over-the-counter products. However, inappropriate exposure to HQ can pose certain health hazards. This study aims to explore the mechanisms of DNA damage and cell apoptosis caused by HQ, with a focus on whether HQ activates the nuclear factor-κB (NF-κB) pathway to participate in this process and to investigate the correlation between the NF-κB pathway activation and poly(ADP-ribose) polymerase 1(PARP1). Through various experimental techniques, such as DNA damage detection, cell apoptosis assessment, cell survival rate analysis, immunofluorescence, and nuclear-cytoplasmic separation, the cytotoxic effects of HQ were verified, and the activation of the NF-κB pathway was observed. Simultaneously, the relationship between the NF-κB pathway and PARP1 was verified by shRNA interference experiments. The results showed that HQ could significantly activate the NF-κB pathway, leading to a decreased cell survival rate, increased DNA damage, and cell apoptosis. Inhibiting the NF-κB pathway could significantly reduce HQ-induced DNA damage and cell apoptosis and restore cell proliferation and survival rate. shRNA interference experiments further indicated that the activation of the NF-κB pathway was regulated by PARP1. This study confirmed the important role of the NF-κB pathway in HQ-induced DNA damage and cell apoptosis and revealed that the activation of the NF-κB pathway was mediated by PARP1. This research provides important clues for a deeper understanding of the toxic mechanism of HQ.

Long non-coding RNA LINC01480 is activated by Foxo3a and promotes hydroquinone-induced TK6 cell apoptosis by inhibiting the PI3K/AKT pathway.

Long non-coding RNAs (lncRNAs) have been shown to play a critical role in the damage caused to the body by environmental exogenous chemicals; however, few studies have explored their effects during exposure to benzene and its metabolite, hydroquinone (HQ). An emerging lncRNA, LINC01480, was found to be associated with the immune microenvironment of some cancers, but its specific function remains unknown. Therefore, this study aimed to investigate the role of LINC01480 in HQ-induced apoptosis. The biological function of LINC01480 was investigated through gain-of-function and loss-of-function experiments. Mechanically, nuclear-cytoplasmic fractionation experiment, chromatin immunoprecipitation (ChIP), dual-luciferase reporter assay, and rescue experiments were performed. In this study, when TK6 cells were treated with HQ (0, 5, 10, and 20 µM) for 12, 24, 48, and 72 h, the expression of LINC01480 was increased in a dose-dependent manner. Meanwhile, the phosphorylation levels of PI3K and AKT decreased, and apoptosis increased. As compared to the control group, HQ-induced apoptosis was significantly reduced, and the relative survival rate of TK6 cells increased after silencing LINC01480, while overexpression of LINC01480 further sensitized TK6 cells to HQ-induced apoptotic cell death. LINC01480 negatively regulated the PI3K/AKT pathway in TK6 cells, and the apoptosis-inhibiting effect of LINC01480 silencing was reversed after inhibition of the PI3K/AKT pathway. In addition, ChIP and the dual-luciferase reporter assays showed that the transcription factor Foxo3a promoted LINC01480 transcription by directly binding to the promoter regions - 149 to - 138 of LINC01480. Moreover, short-term HQ exposure promoted the expression of Foxo3a. From these findings, we can conclude that LINC01480 is activated by Foxo3a, and promotes HQ-induced apoptosis by inhibiting the PI3K/AKT pathway, suggesting that LINC01480 might become a possible target for therapeutic intervention of HQ-induced toxicity.

Mediterranean diet improves embryo yield in IVF: a prospective cohort study.

BACKGROUND: Mediterranean diet (MediDiet) had been reported to be beneficial to human health. However the relationship between diet pattern and outcomes of in vitro fertilization (IVF) treatment was scarcely researched. This study was aimed to explore the correlation between MediDiet pattern of infertile women and their clinical outcomes of IVF cycles. METHODS: An observational prospective cohort study was conducted in the reproductive center from September 2016 to December 2017. Seven hundred infertile women about to undergo IVF treatment were asked to conduct a questionnaire survey. Patients were assigned to higher MediDiet adherence group or lower MediDiet adherence group according to their Mediterranean diet scores. Laboratory parameters and clinical outcomes were compared and those were different between groups were further analyzed for their relationship with MediDiet adherence. RESULTS: A total of 590 women were finally included in the study. According to MediDiet scores, 228 participants were categorized as higher MediDiet adherence group and 362 others as lower MediDiet adherence group. No significant differences were found in baseline characteristics between groups. Higher MediDiet adherence group showed larger number of embryos available (8.40 ± 5.26 vs 7.40 ± 4.71, P = 0.028). Clinical pregnancy rate and implantation rate were similar between the two groups. In further correlation tests and multivariate linear regression analysis, number of fertilized oocytes and embryo yield were positively correlated to MediDiet adherence of participants. CONCLUSION: Infertile women with greater adherence to Mediterranean diet pattern were likely to obtain more embryos available in IVF cycle.

Comparison of different counting chambers using a computer-assisted semen analyzer.

A routine computer-assisted sperm analysis is an important diagnostic test in the andrology laboratory. To evaluate the accuracy and precision of the different types of counting chambers for human semen analysis in combination with a computer-assisted semen analyzer (CASA), a quality-control study that compared human sperm analysis results obtained using different counting chambers (Makler chamber, disposable 8-cell GoldCyto chamber, disposable 4-cell Leja chamber, a plain glass slide, and a tissue culture dish cover with a 24 × 24 mm(2) coverslip) in conjunction with the CASA systems was performed. Significantly higher counts of sperm concentration were obtained from the reusable Makler chamber than from the other counting chambers. Sperm motility from drop loaded counting chambers was significantly higher than that of capillary-loaded chambers. A plain glass slide and a tissue culture dish cover used with a coverslip showed rather better performance in semen assessment. Disposable chambers are suitable for routine semen analysis with CASA in a diagnostic andrology setting. With the proper workflow and quality control, a plain glass slide and the tissue culture dish cover are acceptable alternatives for routine counting chambers with CASA as necessary. The type of counting chamber should be specified in test reports.