Melanogenesis inhibitory effect of Perilla Frutescens (L.) Britt on a hyperpigmentation model in rabbit

Abstract

The study aims to evaluate the melanogenesis inhibitory action of the ethyl acetate (EA) extract from Perilla frutescens (L.) Britt on a hyperpigmented rabbit model induced by UVA-exposure combined to progesterone injection. The dorsal shaved skin of the experimental rabbits was exposed to UVA radiation (386 nm, 147 uW/cm 2 ) in 30 minutes each day for 28 days. Progesterone was intramuscularly injected every other day at the dose of 5 mg/kg. EA extract was topically applied daily from the first day of melasma appearance until the end of the experiment. Morphometric observation based on color thresholder application on MATLAB software. Moreover, melanin determination and histological analysis were also performed. The morphometric observation on the surface of melasma areas as well as the histological analysis from 5% EA-treated group are similar to these of 4% Hydroquinone-treated group at day 14, 21, 28. Melanin concentration in 5% EA-treated group was significantly decreased as compared to the hyperpigmentation group. In conclusion, EA extract of Perilla leaves clearly exhibited the inhibitory effect on melanogenesis in the hyperpigmented rabbit-induced by UVA exposure combined to progesterone injection.