Fig. 11. A possible mechanisms for ceramide alterations in atopic dermatitis (AD). Possible mechanisms may explain for the decreased ceramide content in the stratum corneum of AD patients, such as: (1) a decrease in de novo ceramide synthesis and (2) an increase 1-deoxysphingolipids synthesis. SPT: serine palmitoyltransferase, DHCer desaturase: dihydroceramide desaturase, 1-DeoxySA: 1-deoxysphinganine, 1-DeoxyDHCer: 1-deoxydihydroceramide, 1-DeoxyCer: 1-deoxyceramide, 1-DeoxySO: 1-deoxysphingosine.