A tool to study Rhodenol (Rhododendrol) induced leucoderma (Vitiligo-like lesions)

• Rhododendrol (Rhododenol, RD) created a big problem in Japan, when 14000 induced cases of vitiligo-like lesions were reported.
• It is known that Rhodoendol is cytoxic against melanocytes in a Tyrosinase dependent way cytotoxicity

The authors suggest a new mouse model for the study of this effect:

• hk14-scf/HRM Tg Mice become albino (fully depigmented) through suppression of melanin synthesis through tyrosinase activity
  • with application of 30%RD 3 times per day on the back:
    • depigmentation was visible on day 14
    • Melan A decreased on day 7
  • After stopping the application of RD:
    • Electron Microscopy shows autophagosomes in mouse melanocyte after 4 days.
    • Repigmentation is visible 49 days with recovery of basal melanocytes

Note:

• when applying RD50%, no mean change in the number of malanocytes (per high power filed under the microscope) was seen compared
• with untreated controls (this could suggest that high concentrations are more toxic than
• control albino mice showed no change at 30% or 50% concentration (this suggests that RD activity is specific to melanocytes, more specific to the synthesis of melanin)

Contributors

Dr Christophe Hsu – dermatologist. Geneva, Switzerland

Source of information: p13-18 Abe Y. et al. A mouse model of leukoderma induced by Rhododendrol (Rhododenol). JSID Annual Meeting (Japanese Society of Investigative Dermatology, 日本研究皮膚科学会) 2014 – Osaka, Japan