Oral administration of glucosylceramide ameliorates inflammatory dry-skin condition in chronic oxazolone-induced irritant contact dermatitis in the mouse ear.
BACKGROUND
Irritant contact dermatitis (ICD) is an inflammatory skin disease triggered by exposure to a chemical that is toxic or irritating to the skin. A major characteristic of chronic ICD is an inflammatory dry-skin condition with associated itching. Although glucosylceramide (GlcCer) is known to improve the skin barrier function, its mechanism of action is unknown.


OBJECTIVE
Using a mouse model of oxazolone-induced chronic ICD, this study investigated the effects of oral administration of GlcCer on inflammatory dry skin.


METHODS
Chronic ICD was induced by repeated application of oxazolone in mice. GlcCer was orally administered once daily throughout the elicitation phase. The beneficial efficacy of GlcCer on cutaneous inflammation was evaluated by assessing ear thickness, lymph node weight, histological findings, and mRNA expression of pro-inflammatory cytokines such as IL-1β and IL-6. Additionally, parameters of the itch-associated response, including scratching behavior, water content of the skin, and aquaporin-3 levels in the lesional ear, were measured.


RESULTS
Oral GlcCer administration significantly suppressed mRNA expression of the pro-inflammatory cytokines IL-1β and IL-6. GlcCer also suppressed ear swelling, lymph node weight gains, and infiltration of leukocytes and mast cells in ICD mice. In oxazolone-induced ICD mice, GlcCer significantly inhibited irritant-related scratching behavior and dehydration of the stratum corneum, and decreased aquaporin-3 expression.


CONCLUSIONS
Our results indicate that GlcCer suppressed inflammation not only by inhibiting cytokine production but also by repairing the skin barrier function, suggesting a potential beneficial role for GlcCer in the improvement of chronic ICD.
Acupuncture and Meridian Science Research Center, Kyung Hee University, Hoegi-dong, Dongdaemoon-gu, Seoul 130-702, Republic of Korea.
Mijung
M
Yeom
Sung-Hun
SH
Kim
Bombi
B
Lee
Jeong-Jun
JJ
Han
Guk Hoon
GH
Chung
Hee-Don
HD
Choi
Hyejung
H
Lee
Dae-Hyun
DH
Hahm
D000284:Administration, Oral; D000818:Animals; D051400:Aquaporin 3 / Q000378:metabolism; D003877:Dermatitis, Contact / Q000188:drug therapy* / Q000378:metabolism*; D017453:Dermatitis, Irritant / Q000188:drug therapy* / Q000378:metabolism*; D004423:Ear / Q000473:pathology; D005963:Glucosylceramides / Q000008:administration & dosage* / Q000378:metabolism; D007249:Inflammation / Q000188:drug therapy*; D053583:Interleukin-1beta / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D008198:Lymph Nodes / Q000473:pathology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008954:Models, Biological; D010081:Oxazolone / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D012867:Skin / Q000378:metabolism
D005963:Glucosylceramides; D053583:Interleukin-1beta; D015850:Interleukin-6; D012333:RNA, Messenger; D010081:Oxazolone; D051400:Aquaporin 3