Figure 2.

Epidermal keratinocytes cell size and osmolyte transporters SMIT and TAUT are decreased with either intrinsic or extrinsic aging. E‐cadherin immunofluorescence stain in (a, b) young and (c, d) aged photoprotected and photoexposed human skin. Morphological assessment of epidermal keratinocyte cell (e) area and (f) diameter in human skin. (g‐j) SMIT immunofluorescence in young and aged, photoprotected and photoexposed skin. (k) SMIT protein expression was significantly downregulated in photoexposed skin compared to photoprotected skin (young p < .0001 and aged p = .0002). (l‐o) TAUT immunofluorescence in young and aged, photoprotected and photoexposed skin. (j) TAUT protein expression was significantly lower in aged skin compared to young skin (photoprotected p = .0462 and photoexposed p < .0001). TAUT protein expression is also significantly downregulated in aged photoexposed skin compared to aged photoprotected skin (p = .0011). Data expressed as mean ± SD (two‐way ANOVA), young n = 5, aged n = 6. Scale bars = 20 µm. SMIT, sodium‐coupled myoinositol transporter; TAUT, taurine transporter