Capillary Electrophoresis Analysis Of Xylitol Selenite-induced Apoptosis In Cancer Cells

Yutangba, one of the typical high-selenium (Se) areas, is located in Enshi City, Hubei Province. To exploit selenium resources and its physiological functions, many Se-rich green products have been promoted. Selenium, an essential trace element for mammals, can protect against cancer. And the anticancer activities are affected by the forms and doses. Sodium selenite, inhibiting carcinogenesis, is one of the earliest and most extensively studied selenium compounds. Xylitol selenite is a new chemosynthesis organic selenium compounds.Firstly, the research focused on testing inhibition effects of xylose selenite and sodium selenite on SMMC-7221cells and their effects on inducing apoptosis. The results indicated that xylitol selenite and sodium selenite could decrease the proliferation of SMMC-7221cells significantly. Besides, tumor-suppressor ability of xylitol selenite was higher than that of sodium selenite. In slab gel electrophoresis,"DNA ladder" could be detected in the presence of xylitol selenite, but not appeared in control group and sodium selenite-treated group.Secondly, separation conditions of DNA were optimized by dynamic sieving capillary electrophoresis. Conditions included injection time, voltage, injection mode, detection limit concentration, temperature, pH, the concentrations of HPMC and mannitol. The calibration curve was established.Thirdly, it focused on dynamic sieving capillary electrophoresis analysis of xylitol selenite-induced apoptosis. Multiples of two different nucleosomes (140bp and180bp) were formed in the presence of xylitol selenite. Sodium selenite had no obvious effect on apoptosis of SMMC-7221cells.The anticancer effects of xylitol selenite were analysised by MTT assay, slab gel electrophoresis and capillary electrophoresis. It indicated cell death occurred due to apoptosis in the presence of xylitol selenite, instead of necrosis. Besides, tumor-suppressor ability of xylitol selenite was higher. The described method was useful in elucidating the anticancer activities of xylitol selenite and other selenium compounds.