Abstract:
Objective To investigate the effect of mono(2-ethylhexyl)phthalate (MEHP) on pluripotency-related transcription factors of mouse embryonic stem cells (mESCs).
Methods Designed concentrations of MEHP (0, 0.1, 1, 10, 100, and 1 000 μmol/L, respectively) were administered to mESCs for 4 d. Cell morphology was observed and cell apoptosis was detected by flow cytometry. The differentiation of mESCs was detected by alkaline phosphatase staining. The expressions of pluripotency-related transcription factors SOX2 and OCT4 genes and proteins in embryonic stem cells were detected by real-time PCR and Western blot respectively.
Results With the increase of exposure dose, the clonal cell clusters of mESCs were shrunk and cell count reduced, especially in the 1 000 μmol/L MEHP group; compared with the control group, the apoptosis rate of mESCs rised with increasing concentration and only elevated significantly in the 1 000μmol/L MEHP group(9.58±2.02)% (P < 0.05). Alkaline phosphatase staining revealed that the mESCs in the 1 000 μmol/L group were lighter or even not stained, indicating differentiation tendency, while the cells in other groups were dyed dark blue or blueviolet. Compared with the control group, the SOX2 and OCT4 gene expressions in the 100 and 1 000 μmol/L groups decreased (Ps < 0.05), and the SOX2 and OCT4 protein expressions in the 1 000 μmol/L group decreased (Ps < 0.05).
Conclusion MEHP at certain concentrations is cytotoxic to mESCs, inhibits mESCs growth, and decreases the expressions of pluripotency-related transcription factors SOX2 and OCT4 in mESCs, which may affect early development of embryos.