Stratum basale. Fold Change in AQP Protein. Stratum corneum. *. ● Identify compounds that stimulate aquaporin-3 expression and activity in skin cells. ● Determine whether identified materials promote a skin moisturizing benefit in humans when formulated into product. *.
Fold Change in AQP Protein
● Identify compounds that stimulate aquaporin-3 expression and activity in skin cells.
● Determine whether identified materials promote a skin moisturizing benefit in humans when formulated into product.
In vivo Dry Skin Grade Improvements
(vs. moisturizer alone)
% Increase in Glycerol Transport
Modulation of Aquaporins to Deliver Consumer Benefits: Applications for Skin Care
E. A. Jewell-Motz, Ph.D., J. R. Kaczvinsky, Ph.D., K. M . Lammers, M.S., S. Xie, Ph.D., R. M. Osborne, Ph.D
P&G Beauty , Cincinnati, Ohio USA
Caffeine Stimulates AQP3 Protein Expression in vitro
AQP3 levels decrease with age
Aquaporins (AQP) are an important class of proteins that regulate the transport of water and other small solutes across plasma membranes. First discovered in the early 1990’s (1), there are now 13 distinct AQP family members that have been identified in a variety of mammalian tissues, many of which are relevant to the consumer products industry. In particular, two aquaporins (AQP3 and AQP9) are expressed in human skin cells (2, 3). AQP3 has been implicated as playing a key role in the transport and distribution of epidermal water and glycerol (3,4) and the regulation of keratinocyte differentiation (5), both critical processes for maintaining skin hydration, barrier function and overall skin health.
Product Formulated with CaffeineDelivers Skin Moisturization Benefit in Human Clinical Studies
Caffeine Stimulates AQP3 Activity in vitro
●40 female subjects
●4 test sites per leg (8 total per subject), 5x4 cm2 area, 2 ul/cm2, total 40 ul treatment twice/day except weekends- 1x per day
●Assessments performed at baseline, 1, 2, and 3 weeks then 2, 7, and 11 day regression assessments
●Technical measures via expert visual grading for dryness and redness,
●Panelists were asked not to consume caffeine or herbal drinks
Glycerol Transport Assay
● MatTek’s Epiderm cultures were treated with test compound for 48 hours before adding glycerol to the medium in the lower chamber.
● Glycerol levels within the upper chamber medium were determined 24 hours later (Free Glycerol Reagent, Sigma, St. Louis, MO).
● Measurement in the glycerol assay was converted into a percentage increase over the control (where the control is equal to 100%). Each mean and SEM were derived from at least three separate experiments, performed in duplicate.
(Science 17 October 2003:Vol. 302. no. 5644, pp. 383 – 384)
AQP3 is localized to