Synergy between ascorbate and α-tocopherol on fibroblasts in culture

Ascorbate and tocopherol are important antioxidants that protect cells against oxidative stress. The interaction of ascorbate and α-tocopherol in cells is difficult to detect as both ascorbate and α-tocopherol are unstable in vitro in a biological medium. We examined the interactions between human dermal fibroblasts, ascorbate and α-tocopherol to determine the effects of the vitamins on growth and cell viability. The interaction of ascorbate and α-tocopherol was studied in a fibroblast culture medium during 48h. Ascorbate and α-tocopherol were detected by fluorimetry after high-performance liquid chromatography (HPLC). Cell growth and cell viability were studied by cell numeration after trypan blue staining. The ascorbate concentration fell in presence of α-tocopherol in cell culture medium under all experimental conditions, with or without cells. Ascorbate partly protected α-tocopherol but only in presence of cells. Cell viability was preserved by α-tocopherol whereas ascorbate enhanced fibroblast growth. The synergy between ascorbate and α-tocopherol corresponds to a consumption of ascorbate which spares α-tocopherol but only in presence of cells.