Intramelanocytic Acidification Plays a Role in the Antimelanogenic and Antioxidative Properties of Vitamin C and Its Derivatives

Figure 8

Expression levels of SVCT-2 mRNA and protein in MCs. MCs were seeded in 6-well plates and were then exposed to 3 J/cm² UVA irradiation in the presence or absence of 1 mM VC. (a) The mRNA level of SVCT-2 was measured using qPCR as detailed in Materials and Methods. (b) The protein level of SVCT-2 was analyzed by western blotting using an anti-SVCT-2 antibody. GAPDH was used as a loading control. Representative blots are shown. Data are shown as of three independent experiments. , compared to the untreated control. (c) For inhibiting SVCT-2, phloretin (a putative SVCT-2 inhibitor) was purchased from Selleck Chemicals (Cat# S2342, Shanghai, China). All compounds were first dissolved in dimethyl sulfoxide (DMSO) and then diluted with PBS into the indicated concentrations. The concentration of phloretin was confirmed to be nontoxic by a cell viability assay. Cells were treated and then stained with AO using the same procedure described in Figure 4. The equal volume of DMSO in PBS was used as a solvent control. Red fluorescence intensity (arbitrary units (A.U.)) for AO staining was measured using ImageJ. Histogram shows the results determined on 50 cells which are presented as for three independent experiments. , versus only VC treatment. Representative immunofluorescence images are shown in the bottom. Scale bar: 10 μm.

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