Rhododendrin inhibits toll-like receptor-7-mediated psoriasis-like skin inflammation in mice.

Abstract

Many active compounds present in Rhododendron brachycarpum have been used in traditional Oriental medicine for the treatment of various skin diseases. However, the precise mechanism of action of the compounds isolated from R. brachycarpum and their relevance as therapeutics for the treatment of psoriasis remain elusive. In this study, we report that rhododendrin isolated from R. brachycarpum strongly inhibits imiquimod (IMQ)-induced psoriasis-like skin inflammation in mice. We showed that topical treatment with rhododendrin reduces IMQ-induced skin hyperplasia, inflammatory mononuclear cell infiltration and the expression of pro-inflammatory mediators in mouse skin. In addition, we found that rhododendrin inhibits the activation of the TLR-7/NF-κB and mitogen-activated protein kinase pathways in both IMQ-induced psoriasis-like skin inflammation in mice and in normal human epidermal keratinocytes treated with IMQ. These results suggest that rhododendrin has an anti-inflammatory effect and can be used as a therapeutic to fight against psoriasis and other inflammatory skin diseases.

• Authors: Yoon-Jae Jeon, Shyam Kishor Sah, Hee Seung Yang, Ji Hae Lee, Jongheon Shin, Tae-Yoon Kim
• Journal: Experimental & molecular medicine (Exp Mol Med) Vol. 49 Issue 6 Pg. e349 (06 30 2017) ISSN: 2092-6413 [Electronic] United States
• PMID: 28665921 (Publication Type: Journal Article)

Chemical References

• Aminoquinolines
• Anti-Inflammatory Agents
• Cytokines
• Glycosides
• Membrane Glycoproteins
• NF-kappa B
• Phenols
• RNA, Messenger
• Tlr7 protein, mouse
• Toll-Like Receptor 7
• rhododendrin
• Imiquimod

Topics

• Aminoquinolines (pharmacology)
• Animals
• Anti-Inflammatory Agents (pharmacology, therapeutic use)
• Cytokines (genetics, metabolism)
• Disease Models, Animal
• Glycosides (pharmacology, therapeutic use)
• Humans
• Imiquimod
• Keratinocytes (drug effects)
• Membrane Glycoproteins (antagonists & inhibitors)
• Mice
• Mice, Inbred C57BL
• NF-kappa B (metabolism)
• Phenols (pharmacology, therapeutic use)
• Primary Cell Culture
• Psoriasis (chemically induced, drug therapy, pathology)
• RNA, Messenger (genetics)
• Rhododendron (chemistry)
• Skin (drug effects, pathology)
• Toll-Like Receptor 7 (antagonists & inhibitors)