Endocrine Abstracts

Objective: To investigate the influence of vitamin E (VE) and selenium (Se) on apoptosis of human thyrocyte induced by H₂O₂.

Methods: The human thyroid epithelium cells (TEC) from normal para-adenoma tissues of patients with thyroid adenoma resection were cultured. In prevention groups, vitamin E (50 μmol/l), selenium (10–7 mol/l) or serum-free medium was respectively added into thyrocytes of monolayer culture before H₂O₂ (200–800 μmol/l) with different concentrations added, while in treatment groups H₂O₂ (200–800 μmol/l) was added firstly. The survial rates of thyrocyte were detected by MTT stain, and the apoptosis rates by flow cytometry.

Results: When the thyroid epithelium cells exposed to H₂O₂ (200–800 μmol/l) only for 24 h, the cell survial rates declined and cell apoptosis rates increased (P<0.01) in both prevention and treatment groups, with a relation of dose-effect response. Adding VE (50 μmol/l) and Se (10–7 mol/l) into cell culture for prevention and treatment, the cell survial rates increased and the thyrocyte apoptosis reduced compared to the corresponding simple H₂O₂ intervention groups. Above differences were particularly significant (P<0.05) when thyrocytes exposed to 400 and 800 μmol/l H₂O₂. The decrease of cell apoptosis rates in group with selenium pre-intervention was more significant than that in group with VE pre-intervention (P=0.018) when cells exposed to 400 μmol/l H₂O₂. While the decline in group with VE was more obvious than that in group with selenium (P<0.05) when cells exposed to 200 and 400 μmol/l H₂O₂ in treatment groups.

Conclusion: VE and selenium could have protective effect on apoptosis of human thyrocytes induced by H₂O₂ in human thyrocytes.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.