Application of mutagen sensitivity assay in a glioma case-control study

Investigation of cellular effects of thymoquinone on glioma cell

Glioblastoma, as an invasive tumor, is one of the most common primary malignant brain tumors. Despite maximum aggressive treatment, patients with glioblastoma have a dismal prognosis. Thymoquinone (TQ) has been found to show anti-cancer effects on different types of cancer. There are a few in vitro studies on the effect of TQ on glial tumors. However, the molecular mechanism of TQ's anti-cancer effect has not been fully elucidated. In the present study, we aimed to investigate the genotoxic, apoptotic, and cytotoxic effects of TQ on C6 rat glioma cells. C6 glioma cells were analyzed after 24 h of exposure to different concentrations of TQ by the ATP cell viability assay for cytotoxicity, comet assay for genotoxicity, 2',7'dichlorodihydrofluorescein diacetate (H2DCF-DA) for intracellular reactive oxygen species (iROS) generation, 3.3'dihexyloxacarbocyanine iodide (DiOC6(3)) for mitochondrial membrane potential, GSH/GSSG-Glo Assay for glutathione level and Fura-2AM for intracellular calcium levels. Apoptosis induction was studied by acridine orange/ethidium bromide double staining, flow cytometry, and western blotting analyses. Caspase-3, Caspase-9, Bax, Bcl-2, and pSTAT3 protein levels were determined by the western blotting method. Cytotoxicity was enhanced by TQ in C6 glioma cells in a concentration-dependent manner. TQ also induced DNA damage, apoptosis, and increased iROS. Also, MMP and GSH levels were decreased by TQ. It inhibited pSTAT3, resulting in apoptosis induction through the regulation of anti-apoptotic and pro-apoptotic proteins. Our results suggest that TQ would be an effective treatment in glioma. Further studies should support these findings.

Influence of cryopreservation on the CATSPER2 and TEKT2 expression levels and protein levels in human spermatozoa

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The cryopreservation process could lead to a reduction in the expression levels of the CATSPER2 and TEKT2 gene in human spermatozoa.

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The cryopreservation process could lead to a down-regulation in the expression of CATSPER2 and TEKT2 gene in human spermatozoa.

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The cryopreservation process could lead to a reduction in the level of CatSper 2 and Tektin 2 protein in human spermatozoa.

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The CatSper 2 and Tektin 2 may be used as markers to explain the causes of motility loss in the spermatozoa after the cryopreservation process.

This study designed to assess the expression level of CATSPER2 and TEKT2 and to evaluate the levels of CatSper2 and Tektin2 proteins in human spermatozoa before and after cryopreservation. One hundred and twenty semen samples were included in this study. All the samples were subjected to qPCR and Western blot analysis. The results showed a significant reduction in the expression levels of CATSPER2 and TEKT2 in the cryopreserved compared to the fresh samples (P = 0.0039 and P = 0.0166, respectively), and the results showed down-regulation in the expression level of CATSPER2 and TEKT2 genes between the study groups. Moreover, the protein levels of the CatSper2 and Tektin2 were lower in cryopreserved samples compared to fresh samples (P = 0.0001). In conclusion, the reduction in the proteins level and expression level of the CATSPER2 and TEKT2 in cryopreserved samples could be used as an indicator of sperm motility loss.