The Effect of Bentonite and Glycolic Acid on the Stratum corneum

Kim, San; Hwang, Sang Min; Choi, Eung Ho; Ahn, Sung Ku; Lee, Seung Hun

Abstract

BACKGROUND
Bentonite clay, which is a major component of mud pack, has been used for various purposes in cosmetics. Glycolic acid is known to be effective in the treatment of acne. Al-though those products are used widely, information on the mode of action and effects on the skin are little and controversial till now.
OBJECTIVE
To investigate whether bentonite alone, or bentonite with glycolic acid in mixed formulation affect the stratum corneum leading to alteration on cutaneous barrier function and whether those products alter the lipid lamellae and desmosomes of corneocytes.
MATERIALS AND METHODS
Mud pack-type ointment of bentonite, bentonite and 5% glycolic acid formulation, bentonite and 10% glycolic acid formulation were applied on the volar fore-arm of the five healthy men and flank skin of five 6-8 week old hairless mice. Transepidermal water loss and capacitance were measured. Electron microscopic examination after ruthenium tetroxide postfixation was performed on the flank skin of the mice.
RESULTS
Transepidermal water loss(TEWL) increased immediately and normalized 4 to 6 hours later after removal of vapor permeable membrane in both mouse and human. Capacitance did not show any evidence of change in the water content of the stratum corneum. Electron microscopic examination revealed that lipid lamellae and desmosome of corneocytes were not de-graded, but lamellar body secretion and partially electron-lucent material was-increased in 10% glycolic acid and bentonite mixture-treated area.
CONCLUSION
Barrier function of stratum corneum is not disturbed by bentonite and glycolic acid formulations at the concentration used. Barrier structures are not disrupted, but lamellar body secretion and partially electron-lucent material was increased by bentonite and glycolic acid formulations at higher concentration.