[Evaluation of skin-moisturizing effects of oral or percutaneous use of plant ceramides].
This study was undertaken to evaluate the assay performance of two methods for measuring the water-holding capacity of the skin: Skicon-200 and Tewameter which determine the water content in the stratum corneum and transepidermal water loss, respectively. Based on these findings, we studied the effects of newly developed skin moisturizers made of plant ceramides. The within-run as well as day-to-day reproducibility of the methods were both satisfactory. When rice-derived NIPPN ceramide RC was used topically for 3 weeks by 23 healthy volunteers, the water content in the stratum corneum of the leg was significantly increased to 141% of the baseline value in comparison with that after placebo use (111%) (p < 0.05), and the transepidermal water-loss was significantly suppressed to 23% of the baseline in comparison with that after placebo use (39%) (p < 0.01). When 20 mg or 40 mg/day of corn-derived NIPPN ceramide CP was given orally for 3 weeks, the water content in the stratum corneum of the leg was significantly increased to 290% and 394% of the baseline value, respectively, in comparison with that after placebo administration (141%) (p <0.05), and the transepidermal water loss was suppressed to 33 and 14% (p < 0.05) of the baseline values, respectively, in comparison with that after placebo administration (69%). These data by Skicon-200 and Tewameter suggest that the two plant ceramides are promising as skin-moisturizing agents not only for topical use but also for oral use.
Asai
Satomi
S
Department of Laboratory Medicine, Tokai University School of Medicine, Isehara.
Miyachi
Hayato
H
D000284:Administration, Oral; D000287:Administration, Topical; D000328:Adult; D001834:Body Water / Q000378:metabolism*; D002518:Ceramides / Q000008:administration & dosage* / Q000302:isolation & purification / Q000494:pharmacology*; D003879:Dermatologic Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D004817:Epidermis / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012275:Oryza / Q000737:chemistry*; D014870:Water Loss, Insensible / Q000187:drug effects*; D003313:Zea mays / Q000737:chemistry*
D002518:Ceramides; D003879:Dermatologic Agents