ABSTRACT:
Performing skin absorption testing is part of recommended regulatory guidelines in the USA and of global interest to assess safety of exposure to chemicals when applied topically. The Personal Care Council (formally CTFA), the OECD (Organization for Economic Co-Operation and Development), WHO (World Health Organization) and SCCP (Scientific Committee of Consumer Products), have all issued guidelines to address absorption of compounds from cosmetic formulations. The objective of these guidelines is to obtain quantitative and/or qualitative information on the amounts of chemicals that may penetrate the skin transdermally into the blood circulatory system during “real time” use. The absorption of a substance into and through the skin is critical for the assessment of the need to further conduct full pharmacokinetics profile studies. The chemicals tested are not necessarily “actives” but also possible contaminants and excipients such as preservatives, fragrance components and other possible sensitizers.
The 7th amendment to the EU directive which banns animal studies on cosmetic ingredients and finished formulations stimulated the adoption of the OECD skin absorption guidelines as the validated method for this important end point.
Since in vitro studies have been demonstrated to provide reliable, reproducible data, for topically applied formulations when the skin is the target of action it is imperative that an understanding of penetration patterns be developed in order to allow for better product development as well as conservation of both resources and time in the process of product design.
My presentation will describe the importance of evaluating skin absorption of compounds from topically applied formulations. This description is an essential context for safety assessment, mechanistic studies and fundamental to conducting clinical studies. It will also review key parameters in the guidelines and provide tools for further research.

Dr. Dayan earned her Ph.D. in Pharmaceutics from the Hebrew University in Jerusalem specializing in skin delivery. She is currently an Associate Adjunct Professor in the Ernest Mario School of Pharmacy at Rutgers University., and the R&D Director at Lipo Chemicals Inc. During her 23 years of experience she has specialized in a variety of areas related to skin treatment:

• The research and understanding of the interaction between topically applied compounds and the skin.
• Findings in skin biochemistry and especially the upper layer of the skin- the stratum corneum
• Delivery of active compounds into and through the skin and the development of delivery systems to facilitate transport, improve bio-availability and reduce toxicity
• Design and development of topically applied formulations
• Design of clinical studies to substantiate market claims and to assure safety.
• Academic teaching and lecturing
• Industrial experience in both development of active compounds, delivery systems and finished formulations
• Skin absorption studies in vivo and in vitro for safety/ efficacy assessment
• In vitro methodologies for safety assessment of topically applied compounds

Dr. Dayan has received numerous awards of excellence for various papers she has authored. She is the author and co-author more then 100 publications including book chapters and was granted 7 patents. She is also the editor of the “Skin Aging Hand Book” published by Elsevier. Dr. Dayan is a member of the Dermatopharmaceutics Focus Group, and the Abstract Review Committee for the American Association of Pharmaceutical Scientists (AAPS). She is serves as the Educational Chair of the NYSCC Chapter and on the Scientific Advisory Board of Health Beauty America Expo. Dr. Dayan teaches at Rutgers University and is the Director of a variety of courses at the Center for Professional Advancement.

ABSTRACT:

“At the heart of [epigenetics] is a simple but contentious idea
— that genes have a 'memory.' That the lives of your grandparents
— the air they breathed, the food they ate, even the things they saw
— can directly affect you, decades later, despite your never experiencing these
things yourself.” BBC, Ghost in Your Genes.

The rapidly evolving science of epigenetics – the scientific study of the molecular software that turn genes on and off – is changing our understanding of heredity, identity, and disease. Research now shows this software, known collectively as the “epigenome”, dynamically responds to our environment throughout our lifetimes. In fact, epigenetic expression is proving to be one of the primary links between cancer and environmental toxins, diet, stress – and perhaps – cosmetic ingredients. In addition, discoveries in longevity science are now making a direct connection between an individual’s epigenome and the way we age. Wrinkle development, stem cell expression, grey hair, baldness and acne are all potential areas of epigenetic investigation.

Dr. Daniel Weisenberger, Research Assistant Professor in the Department of Biochemistry and Molecular Biology at University of Southern California and project manager at the USC Epigenome Center, will join us in May to discuss the role of epigenetics in human health and disease, and its relevance to the future of the cosmetic industry. Elements of his talk include:

• An overview of basic cellular biology and epigenetics
• The diversification of the human epigenome over different individuals and tissue types
• How epigenetics is altered in human diseases, such as cancer

As Dan notes, “The human epigenome is altered as a function of aging, and there are additional widespread epigenomic changes in human melanomas (skin cancer).” These findings may provide important clues to the cosmetic industry with regards to skin care products and the reversal of signs of aging.

Daniel J. Weisenberger holds two Bachelor’s of Science degrees in Chemistry and Cellular and Molecular Biology from the University of Michigan, and a PhD in Biological Chemistry from Wayne State University. His work has focused on the reactivity of chemical carcinogens with DNA, human cancer epigenetics and technology development. Dan currently has the title of Research Assistant Professor in the Department of Biochemistry and Molecular Biology at USC, and has additional duties in project management for Dr. Peter W, Laird at the USC Epigenome Center. Dan is an expert in DNA methylation and cancer epigenetics and has co-authored more than 30 peer-reviewed publications since arriving at USC in 2000.