Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
Center for General Education, Chang Gung University of Science and Technology, Kweishan, Taoyuan, Taiwan.
AAPS PharmSciTech. 2022 Jul 8;23(6):187. doi: 10.1208/s12249-022-02344-3.
Tea catechins are a group of flavonoids that show many bioactivities. Catechins have been extensively reported as a potential treatment for skin disorders, including skin cancers, acne, photoaging, cutaneous wounds, scars, alopecia, psoriasis, atopic dermatitis, and microbial infection. In particular, there has been an increasing interest in the discovery of cosmetic applications using catechins as the active ingredient because of their antioxidant and anti-aging activities. However, active molecules with limited lipophilicity have difficulty penetrating the skin barrier, resulting in low bioavailability. Nevertheless, topical application is a convenient method for delivering catechins into the skin. Nanomedicine offers an opportunity to improve the delivery efficiency of tea catechins and related compounds. The advantages of catechin-loaded nanocarriers for topical application include high catechin loading efficiency, sustained or prolonged release, increased catechin stability, improved bioavailability, and enhanced accumulation or targeting to the nidus. Further, various types of nanoparticles, including liposomes, niosomes, micelles, lipid-based nanoparticles, polymeric nanoparticles, liquid crystalline nanoparticles, and nanocrystals, have been employed for topical catechin delivery. These nanoparticles can improve catechin permeation via close skin contact, increased skin hydration, skin structure disorganization, and follicular uptake. In this review, we describe the catechin skin delivery approaches based on nanomedicine for treating skin disorders. We also provide an in-depth description of how nanoparticles effectively improve the skin absorption of tea catechins and related compounds, such as caffeine. Furthermore, we summarize the possible future applications and the limitations of nanocarriers for topical delivery at the end of this review article.
茶儿茶素是一组具有多种生物活性的类黄酮。儿茶素已被广泛报道为治疗皮肤疾病的潜在方法，包括皮肤癌、痤疮、光老化、皮肤创伤、疤痕、脱发、银屑病、特应性皮炎和微生物感染。特别是，由于其抗氧化和抗衰老活性，人们对使用儿茶素作为活性成分的化妆品应用的发现越来越感兴趣。然而，亲脂性有限的活性分子难以穿透皮肤屏障，导致生物利用度低。尽管如此，局部应用是将儿茶素递送至皮肤的一种便捷方法。纳米医学为提高茶儿茶素和相关化合物的递送效率提供了机会。儿茶素负载纳米载体用于局部应用的优点包括高儿茶素载药量、持续或延长释放、增加儿茶素稳定性、提高生物利用度以及增强蓄积或靶向作用。此外，各种类型的纳米颗粒，包括脂质体、非离子型脂质体、胶束、基于脂质的纳米颗粒、聚合物纳米颗粒、液晶纳米颗粒和纳米晶体，已被用于局部儿茶素递送。这些纳米颗粒可以通过紧密的皮肤接触、增加皮肤水合作用、皮肤结构紊乱和毛囊摄取来提高儿茶素的渗透。在本综述中，我们描述了基于纳米医学的儿茶素皮肤递药方法，用于治疗皮肤疾病。我们还深入描述了纳米颗粒如何有效地提高茶儿茶素和相关化合物（如咖啡因）的皮肤吸收。此外，我们在本文结尾处总结了纳米载体在局部递送方面的可能未来应用和局限性。
