The effects of excessive selenium metabolism on protein expression of HepG2 cells

Abstract

High selenium (Se) level in the culture medium was reported to delay cell growth and to cause morphological changes of HepG2 cells in our previous study. The purpose of this study was to use proteomic technique to explore the influence of excessive Se metabolism on the protein expression of HepG2 cells. After 24 hr of exposure in 20 μM of sodium selenite in medium, the expression of at least 30 proteins was significantly altered. Nine of the up‐regulated proteins included those participated in immune response (immunoglobulin heavy chain), collagen formation (proline 4‐hydroxylase), energy metabolism (mitochondrial ATP synthase), tumor suppressor protein (prohibitin), cell growth (FUBP1 protein, galectin‐3 carbohydrate recognition domain), and cell differentiation (human nucleoside diphosphate kinase, galectin‐3 carbohydrate recognition domain). The expression of 21 proteins was down regulated, which also included some proteins in the cellular activities such as energy metabolism, immune response, DNA replication (EF‐Tu) and cytoskeleton. Therefore alterations in protein expression occurred in the early phase of high Se exposure may be related to the later changes in the growth and morphology of HepG2 cells. Further analysis regarding the systemic relationship among the aforementioned proteins and many others is currently underway. (Sponsored by Office of Research and Development, Fu Jen Catholic University, Project 409531060439)