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Topically applied hypericin exhibits skin penetrability on nude mice
Zhuo-Heng Li1,2,3, Yuan-Yuan Li4, Min Hou4
1College of Pharmaceutical Sciences and Chinese Medicine, Southwest University, Chongqing, 400715, People's Republic of China.
Lasers in Medical Science
|June 20, 2018
Summary
Topical hypericin efficiently penetrates nude mouse skin, showing potential for photodynamic therapy (PDT) in treating skin diseases. Menthol enhances hypericin
Area of Science:
- Dermatology
- Photochemistry
- Pharmacology
Background:
- Hypericin is a natural photosensitizer used in photodynamic therapy (PDT).
- Topical PDT aims to treat skin diseases with reduced systemic side effects.
- Skin penetrability of topical hypericin requires optimization for effective PDT.
Purpose of the Study:
- To evaluate the skin penetrability of topically applied hypericin.
- To assess the efficacy of menthol as a penetration enhancer for hypericin.
- To investigate the therapeutic potential of topical hypericin-PDT for skin conditions.
Main Methods:
- Franz diffusion cell assays to screen penetration enhancers.
- In vivo studies on nude mice using hypericin gel with and without menthol.
- Fluorescence microscopy, macroscopic and microscopic skin analysis, and immunohistochemistry (PECAM-1 expression).
Main Results:
- Menthol significantly enhanced hypericin penetration into nude mouse skin.
- Topical hypericin penetrated the dermis, causing a photosensitivity reaction in dermal capillaries.
- Skin damage from hypericin-PDT was repaired within 7 days, with normal skin regeneration.
Conclusions:
- Topical hypericin demonstrates effective skin penetration and PDT potential.
- Menthol is an effective enhancer for topical hypericin delivery.
- Topical hypericin-PDT offers a promising treatment strategy for skin diseases involving capillary proliferation.
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