Shiseido Co. has found that Japanese cedar pollen can impair the barrier functions of human skin.
It is widely known that cedar pollen causes allergic reactions affecting the eyes and sinuses, but the major cosmetics maker has now proven that the pollen allergen disrupts the skin as well.
In its research, Shiseido cultured human skin tissue and removed a surface layer called the stratum corneum.
The tissue was then exposed to either pure water or a water solution containing the pollen allergen. Water evaporated from the solution-exposed tissue far more rapidly, meaning the barrier functions weakened, Shiseido said.
Cedar pollen can cause skin inflammation, especially when skin barrier functions have weakened due to stress or other factors, said Mitsuhiro Denda, a senior researcher at Shiseido’s Life Science Research Center.