Aloesin

In a wide-ranging study of the anti-inflammatory and antioxidant properties of various aloe isolates, including cinnamoyl, p-coumaroyl, feruloyl, caffeoyl aloesin, and related compounds, Yagi et al. found that the involvement of the caffeoyl, feruloyl, and coumaroyl groups bound to aloesin was well established, and the contact hypersensitivity response suggested that aloesin prevented UVB-induced immune suppression. In addition, they noted that aloesin inhibited the tyrosine hydroxylase and DOPA oxidase activities of tyrosinase in normal human melanocyte cell lysates (Yakugaku Zasshi 2003;123:517-32).

Importantly, the Ames test has not shown any genotoxicity or mutagenicity to be associated with aloesin and cell-based assays have revealed no cytotoxicity linked to the Aloe derivative (Dermatol. Clin. 2007;25:353-62).

Conclusion

Aloesin is a less effective but safe alternative to the use of hydroquinone in the treatment of unwanted hyperpigmentations. Used in combination with other skin-lightening agents, aloesin contributes to treatments that rival hydroquinone in effectiveness. Recent research appears to indicate that greater potential for aloesin as a hypopigmenting ingredient is yet to be realized. Of course, much more research is necessary to determine whether aloesin has a larger and more independent role to play in cosmetic and therapeutic hypopigmentation regimens. At this juncture, this botanical derivative is a useful adjuvant in the dermatologic armamentarium.

This column, Cosmeceutical Critique, regularly appears in Skin and Allergy News, an Elsevier publication. Dr. Baumann is in private practice in Miami Beach. She did not disclose any conflicts of interest. To respond to this column, or to suggest topics for future columns, write to her at sknews@elsevier.com.