Cosmeceutical Critique

Review of plant phenolics, part 3: Nonflavonoid compounds

Publish date: November 1, 2017

Condensed tannins (Proanthocyanidins): pycnogenol

Pycnogenol has been used in an antioxidant mixture also including vitamins C and E, as well as evening primrose that when orally administered for 10 weeks to female SKH-1 hairless mice exposed three times weekly to UVB irradiation demonstrated the capacity to significantly inhibit wrinkle formation by markedly suppressing UVB-induced MMP activity while promoting collagen production.¹⁹ In a 2012 study of 112 women with mild to moderate photoaging, orally administered pycnogenol was shown to yield significant reductions in clinical grading of skin photoaging scores.²⁰ Four years later, a review by Grether-Beck et al. suggested that oral administration of pycnogenol imparts photoprotection, diminishes hyperpigmentation, and improves skin barrier function and the stability of the extracellular matrix.²¹

Lignins: various woody plants

Recognized as efficient natural scavengers of reactive oxygen species, lignins are complex phenolic polymers that are abundant in nature, particularly in various tree species and agricultural products. In 2004, Dizhbite et al. isolated lignin samples from deciduous and coniferous trees to assess their capacity as natural antioxidants. Samples were assessed against the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical in homogeneous conditions, with the commercially available kraft lignin noted for displaying antibacterial activity associated with its radical-scavenging properties.²² Four years later, Ugartondo et al. studied several lignins and reported a strong antioxidant capacity at various concentrations that were innocuous to normal human cells and stable when exposed to UVA. The investigators concluded that lignins may be viable for inclusion in cosmetic and topical medical formulations.²³

Conclusion

A brief survey of the polyphenolic landscape obviously cannot do the subject justice. From the dermatologic perspective, this diverse family of compounds factor into the skin care formulations becoming more prevalent in the established armamentarium, as well as the direct-to-consumer market. Given the increasing attention paid here and elsewhere to the impact of diet on the skin, the status of this dynamic class of polyphenolic compounds, which includes several antioxidants and is found in numerous plants, appears to be well deserved and warrants much more research.

Dr. Baumann is a private practice dermatologist, researcher, author and entrepreneur who practices in Miami. She founded the Cosmetic Dermatology Center at the University of Miami in 1997. Dr. Baumann wrote two textbooks: “Cosmetic Dermatology: Principles and Practice” (New York: McGraw-Hill, 2002), and “Cosmeceuticals and Cosmetic Ingredients,” (New York: McGraw-Hill, 2014), and a New York Times Best Sellers book for consumers, “The Skin Type Solution” (New York: Bantam Dell, 2006). Dr. Baumann has received funding for advisory boards and/or clinical research trials from Allergan, Evolus, Galderma, and Revance. She is the founder and CEO of Skin Type Solutions Franchise Systems LLC.