FIGURE 6.

Skin barrier recovery of Aldh3a2^−/− mice is delayed. A and B, lipids were extracted from the epidermis of wild-type and Aldh3a2 KO mice at P0, and ceramide (A) and acylceramide (B) species were analyzed by LC/MS/MS. Values are the amount of each ceramide species containing C18:0 sphingosine and FAs with the indicated chain length (A) or that of acylceramide species containing C18:0 sphingosine, linoleic acid, and FAs with the indicated chain length (B). They represent the means ± S.D. from four independent reactions. C, wild-type and Aldh3a2 KO mice at P0 were stained with 0.1% toluidine blue for 24 h and photographed. D, TEWL was measured for the wild-type and Aldh3a2 KO mice at P0. Values represent the means ± S.D. from eight wild-type or six Aldh3a2 KO independent mice. E and F, the skins of wild-type and Aldh3a2 KO mice at P0 were treated with acetone or saline as a control. TEWL was measured after acetone treatment (0 h, E and F; 1 h, F; 3 h, F). Values are TEWL amounts (E). In F, barrier recovery is expressed in terms of TEWL, with TEWL at 0 h after acetone set as 0% and TEWL before acetone treatment as 100%. Values represent the means ± S.D. of five wild-type or four Aldh3a2 KO mice in independent experiments. Statistically significant differences between wild-type and Aldh3a2 KO mice are indicated (**, p < 0.01; *, p < 0.05; Student's t test).