Ascorbic acid inhibits TPA-induced HL-60 cell differentiation by decreasing cellular H2O2 and ERK phosphorylation

Abstract

Retinoic acid (RA), vitamin D and 12-O-tetradecanoyl phorbol-13-acetate (TPA) can induce HL-60 cells to differentiate into granulocytes, monocytes and macrophages, respectively. Similar to RA and vitamin D, ascorbic acid also belongs to the vitamin family. High-dose ascorbic acid (>100 μM) induces HL-60 cell apoptosis and induces a small fraction of HL-60 cells to express the granulocyte marker, CD66b. In addition, ascorbic acid exerts an anti-oxidative stress function. Oxidative stress is required for HL-60 cell differentiation following treatment with TPA, however, the effect of ascorbic acid on HL-60 cell differentiation in combination with TPA treatment remains to be fully elucidated. The aim of the present study was to investigate the cellular effects of ascorbic acid treatment on TPA-differentiated HL-60 cells. TPA-differentiated HL-60 cells were used for this investigation, this study and the levels of cellular hydrogen peroxide (H2O2), caspase activity and ERK phosphorylation were determined following combined treatment with TPA and ascorbic acid. The results demonstrated that low-dose ascorbic acid (5 μM) reduced the cellular levels of H2O2 and inhibited the differentiation of HL-60 cells into macrophages following treatment with TPA. In addition, the results of the present study further demonstrated that low-dose ascorbic acid inactivates the ERK phosphorylation pathway, which inhibited HL-60 cell differentiation following treatment with TPA.