Vitamin E ointment at high dose levels suppresses contact dermatitis in rats by stabilizing keratinocytes.
OBJECTIVE
The pharmacological effect of vitamin E ointment at high dose levels was investigated in rats and mice during the development of contact dermatitis.


METHODS
Allergic or irritant contact dermatitis was induced in sensitized or unsensitized animals by topical application of chemical agent(s). Cultured keratinocytes were prepared from dorsal skin of rats.


RESULTS
The vitamin E ointment at 20-40% suppressed allergic and irritant contact dermatitis, exerting a comparable effect to that of 0.5% prednisolone ointment. Microscopic findings revealed that 20% vitamin E ointment reduced the keratinocyte damage, whereas 0.5% prednisolone was ineffective. The protective action of vitamin E on keratinocyte damage was also confirmed in a cell culture experiment. Furthermore, 20% vitamin E ointment blocked down-regulation of skin barrier function induced by contact dermatitis, although 0.5% prednisolone ointment was inactive.


CONCLUSIONS
These results indicate that 20% vitamin E ointment suppresses contact dermatitis by stabilizing keratinocytes, concomitantly with novel, interesting properties.
Kuriyama
K
K
Medical Research Laboratory, Sekisui Chemical Co. LTD, 2-1 Hyakuyama Shimamoto-cho, Mishima-gun, Osaka 618, Japan. kuriyama003@smile2.sekisui.co.jp
Shimizu
T
T
Horiguchi
T
T
Watabe
M
M
Abe
Y
Y
D000287:Administration, Topical; D000485:Allergens / Q000633:toxicity; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000627:therapeutic use; D000975:Antioxidants / Q000008:administration & dosage / Q000378:metabolism / Q000627:therapeutic use*; D015824:Blood-Air Barrier / Q000187:drug effects; D002478:Cells, Cultured; D003877:Dermatitis, Contact / Q000188:drug therapy* / Q000473:pathology; D004137:Dinitrochlorobenzene / Q000633:toxicity; D005079:Excipients; D007509:Irritants / Q000633:toxicity; D015603:Keratinocytes / Q000187:drug effects* / Q000473:pathology; D008297:Male; D009824:Ointments; D011239:Prednisolone / Q000008:administration & dosage / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar; D012867:Skin / Q000187:drug effects / Q000378:metabolism; D014810:Vitamin E / Q000008:administration & dosage / Q000378:metabolism / Q000627:therapeutic use*
D000485:Allergens; D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D004137:Dinitrochlorobenzene; D005079:Excipients; D007509:Irritants; D009824:Ointments; D014810:Vitamin E; D011239:Prednisolone