Schaller M, Steinle R, Korting H C
Department of Dermatology, Ludwig-Maximilians-University, Munich, Germany.
Acta Derm Venereol. 1997 Mar;77(2):122-6. doi: 10.2340/0001555577122126.
The topical application of tretinoin is a well-established approach to the treatment of acne vulgaris. However, induced inflammation, clinically addressed as a "flare-up", is a major drawback. Recently, clinical and experimental investigations have hinted at a better tolerability, with equal efficacy, if the active compound is liposomally encapsulated. Using epidermis reconstructed in vitro, we compared the morphological changes upon topical application of a liposomal form (0.05% and 0.025%) and conventional form (0.05%) light and electron microscopically. After 24 h several remarkable changes of the stratum corneum with all treatment modalities, representing inhibition of keratinisation wanted in acne vulgaris, were seen. When preparations of equal strength, i.e. 0.05%, were compared, the changes representing toxic dermatitis in the epidermis were more marked with the conventional form. Epidermis reconstructed in vitro treated with the liposomal forms showed no significant differences due to either concentration. It is suggested that these changes correspond to the flare-up on clinical grounds. The in vitro findings further corroborate the hypothesis that liposomal encapsulation can increase the benefit/risk ratio of an active compound applied to the skin.
外用维甲酸是治疗寻常痤疮的一种成熟方法。然而，诱发炎症，临床上称为“爆痘”，是一个主要缺点。最近，临床和实验研究表明，如果活性化合物被脂质体包裹，耐受性会更好，疗效相同。我们使用体外重建的表皮，通过光镜和电镜比较了外用脂质体形式（0.05%和0.025%）和传统形式（0.05%）后的形态变化。24小时后，所有治疗方式均使角质层出现了一些显著变化，这表明寻常痤疮中所需的角质化受到抑制。当比较同等强度（即0.05%）的制剂时，传统形式在表皮中表现出的代表毒性皮炎的变化更为明显。用脂质体形式处理的体外重建表皮在两种浓度下均未显示出显著差异。从临床角度来看，这些变化可能与爆痘相对应。体外研究结果进一步证实了脂质体包裹可以提高应用于皮肤的活性化合物的效益/风险比这一假设。
