ABSTRACT
Objective To explore the cytotoxic effects and mechanisms of Aflatoxins B1(AFB1) on the African green monkey kidney cells (Vero E6).Methods After incubation of Vero E6 cells with AFB1,cellular toxicity was assessed by CCK-8 assay and LDH release rate.Annexin V/PI double staining and DAPI staining was used to detected cell apoptosis.Results AFB1 has significant toxic effects on Vero E6 cells.Cell viability was less than 10% when treated by 200 μmol/L AFB1 for 48 h.LDH release rate was increased significantly with the increase of AFB1 concentration.Externalization of cell membrane phosphatidylserine was observed by Annexin V/PI double staining.Nucleus fragmentation was detected by DAPI staining.Conclusion AFB1 exhibits significantly cytotoxic effects on Vero E6 cells by inducing cell apoptosis.
ABSTRACT
Batch and continuous fermentation were adopted to investigate the effect of specific growth rate and amino acid components on RNA accumulation in Candida tropicalis ATCC 20408 in fermentation medium ( FM), yeast peptone dextrose medium (YPD), molasses fermentation medium ( MFM) and FM without corn steep liquor. The data showed that obvious differences in intracellular RNA accumulation were observed at different cell growth phases in bath fermentation prosess, and RNA level reached 11. 8% (g-RNA /g-DCW) during exponential phase, and only 6.9% during stationary phases. It was also found that intracellular RNA accumulation increased with the increase of specific growth rate in continue fermentation prosess, and the highest RNA level reached 15. 6% with the glucose conversion rate of 42. 8% at the dilution rate of 0. 5 h-1. Furthermore, the data showed that RNA lever was notably increased in batch fermentation process when amino acids or peptone was added into the fermentation medium containing no corn steep liquor. Taken together, it was reported for the first time that specific growth rate and amino acid components plays a leading role on the intracellular RNA accumulation in C. tropica lis, and specific growth rate is more important.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the suppressive effect of resveratrol on growth of U251 human glioma cells and its correlated mechanism.</p><p><b>METHOD</b>U251 human glioma cells were treated with resveratrol at various concentrations, MTT assay was used to determine the inhibitory rate of cell proliferation, FCM to detect the cell apoptosis, the expressions of Bcl-2, Bcl-XL, STAT3 and CyclinD1 were analysed by immunohistochemistry and Western blot to examine the expression of Bcl-2, Bcl-XL, STAT3, CyclinD1, Caspase-3 and Bax.</p><p><b>RESULT</b>After treatment with resveratrol, MTT assay showed the growth of U251 cells was inhibited in dose-dependent and time-dependent manners, apoptosis of cells advanced stage was built up, immunohistochemical staining displayed decreased the expression of Bcl-2, Bcl-XL, STAT3 and CyclinD1 and Western blot showed that resveratrol decreased the expression of Bcl-2, Bcl-XL, STAT3 and CyclinD1, and built up Bax and Caspase-3.</p><p><b>CONCLUSION</b>It is possible that downregulated the expression of Bcl-2, Bcl-XL, but upregulated Bax and Caspase-3, and the indication was obviously in dose-dependent and time-dependent manners.</p>