ABSTRACT
This chapter aims to investigate the effects of six different Selenium (Se) species, including selenite, selenate, selenomethionine, L-selenocystine (L-Secys2), Se-methylselenocysteine, Se nanoparticles (SeNPs) on cell viability, oxidative stress, and apoptosis in HepG-2 cells. All six Se compounds increased intracellular reactive oxygen species levels. Se is an essential trace element that is composed a variety of important enzymes. Se compounds induced apoptosis in HepG-2 cells in a dose-dependent manner. Compared with the same dose of Se compounds, the group treated with selenite and L-Secys2 showed higher apoptosis rates compared to other Se compounds. The results indicate that Se can inhibit cancer cells proliferation at higher concentrations and even result in apoptosis. The metabolites of selenite, L-Secys2, and SeNPs induced oxidative stress that contributed to the cytotoxicity in cancer cells. The relationship between low-serum Se levels to a higher cancer risk has attracted considerable attention in the area of cancer prevention.
