%0 Journal Article
%T Effects of Cosmetic Formulations Containing Hydroxyacids on Sun-Exposed Skin: Current Applications and Future Developments
%A Andrija Kornhauser
%A Sergio G. Coelho
%A Vincent J. Hearing
%J Dermatology Research and Practice
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/710893
%X This paper describes recent data on the effects of various skin formulations containing hydroxyacids (HAs) and related products on sun-exposed skin. The most frequently used classes of these products, such as ¦Á- and ¦Â-hydroxyacids, polyhydroxy acids, and bionic acids, are reviewed, and their application in cosmetic formulations is described. Special emphasis is devoted to the safety evaluation of these formulations, particularly on the effects of their prolonged use on sun-exposed skin. We also discuss the important contribution of cosmetic vehicles in these types of studies. Data on the effects of HAs on melanogenesis and tanning are also included. Up-to-date methods and techniques used in those explorations, as well as selected future developments in the cosmetic area, are presented. 1. Introduction The cosmetic market is growing rapidly internationally and shows no sign of slowing in the foreseeable future. Within skin care products, antiaging and sun protection products are the main driving forces in this trend. Contemporary cosmetics contain a large number of active ingredients, such as botanicals, antioxidants, hormones, and hydroxyacids (HAs) to name just a few. In this paper, we focus on the role that HAs play in cosmetic/skin care products, their safety evaluations, and their effects on sun-exposed skin. This paper covers selected new developments in the field which appeared since our previous review of this topic, and it also includes selected topics not covered in that paper [1]. 2. Presentation of HAs Structure and Classification HAs have significantly influenced skin care since their introduction to dermatology about 40£¿yrs ago [2]. Since their inclusion in cosmetic formulations, they have been used to treat acne, ichthyosis, keratoses, psoriasis, photoaged skin and other disorders [3]. Following these developments, HAs have been gradually added into a variety of cosmetic products for daily use and over extended time periods [4]. At present, glycolic acid, lactic acid, and salicylic acid are the most frequently used HAs in cosmetics. One of the most cited beneficial effects of HAs is the reported improvement of photoaged skin. The driving force behind the increase in HAs use in cosmetic dermatology and skin care systems has been their antiaging effects [5]. Based on their structure and function, HAs can be classified as ¦Á-HAs, ¦Â-Has, and salicylic acid (SA) and its derivatives. The most common representative of an ¦Á-HA is glycolic acid, which was one of the first HAs to be incorporated into cosmetic formulations [4]. Another ¦Á-HA being used
%U http://www.hindawi.com/journals/drp/2012/710893/