Purpose: The topical application of scalp-care cosmetics, infused with functional ingredients, can offer an optimal cosmetic approach to prevent problems associated with aging. In terms of the development of anti-aging cosmetics, we studied the use of acetyl hexapeptide-8 (AH-8) for improving elasticity of the scalp.Methods: Ampoules containing 3% and 5% concentrations of AH-8 as an active ingredient were prepared and their safety and efficacy were evaluated. HaCaT cells were used to evaluate the safety of AH-8 ampoules by measurement of in vitro cytotoxicity. In in vivo experiments, we tested the AH-8 ampoules by cumulative irritation test (CIT) on healthy adults, 20–50 years of age. Relative expressions of superoxide dismutase 2 (SOD2), forkhead box O1 (FOXO1), actinin alpha 1 (ACTN1), collagen type XVII alpha 1 chain (COL17A1), and integrin subunit beta 4 (ITGB4) were assessed using quantitative real-time PCR (Q-PCR).Results: AH-8 ampoules showed significant cytotoxicity to HaCaT cells in a dose-dependent manner. CIT assessment in 30 adults revealed no skin reactions to both 3% and 5% AH-8 ampoules. After treatment of HaCaT cells with the AH-8 ampoules, mRNA levels of SOD2 and FOXO1, which are directly implicated as antioxidant factors, were increased. Of the factors that improve elasticity, ACTN1 mRNA levels had the greatest increase when treated with the 5% AH-8 ampoules (1.75 µg/mL). Also, the AH-8 ampoules increased mRNA levels of COL17A1, and ITGB4 in HaCaT cells.Conclusions: In this study, we proved that 3% and 5% AH-8 ampoules are safe for use as a scalp-care cosmetic. AH-8 ampoule had efficacy in anti-aging and improving elasticity of the scalp. This comprehensive test showed that AH-8 can be developed as a cosmetic for anti-aging and improvement of scalp elasticity.

Acetyl hexapeptide-8 (AH-8) is a well-known component of anti-aging products. AH-8 appears in a variety of cosmetic products, its skin penetration is sparsely studied and controversially discussed. This study investigated ampoule containing AH-8 as an active ingredient. The elasticity improving effect of 3% AH-8 ampoule was tested <i>in vivo</i>. To test the stability of the formulated ampoules, we performed the centrifugation, cycling and measured viscosity, and pH changes. 6 weeks-old female C3H mice were purchased from Orient Bio, Korea Inc. (Seongnam, Korea). After one week of acclimatization, the mice were randomly assigned to experimental groups (n=4 for each group); Control, UVB irradiation, Vehicle ampoule, and 3% AH-8 ampoule group. Irradiated with UVB to mouse skin, then 3% AH-8 ampoule were applied into irradiated sites for 6 weeks. Changes in the amount of TGF-β1 and collagen were measured using western blot. As a result, it was confirmed that the 3% AH-8 ampoule increased the expression of TGF-β1 and collagen. In summary, we showed that AH-8 ampoule had extremely high capability of improving elasticity when compared to vehicle ampoule containing ginkgo leaf and green tea extracts. This study revealed the efficacy of AH-8 for increasing skin elasticity and anti-aging in terms of a cosmetic active ingredient.

Purpose: Acetyl hexapeptide-8 (AH-8) had been reportedly effective in improving keratinocytes. Ampoules containing AH-8 as an active ingredient were prepared, and their efficacy for improving skin elasticity was evaluated.Methods: Ampoules containing 3% and 5% AH-8 were prepared, and their efficacy was evaluated. C3H mice were pretreated with different AH-8 ampoule concentrations and then irradiated with UVB for 6 weeks. Changes in the number of collagen and elastic fibers from paraffin-embedded skin tissues were quantitatively measured using an image analysis program.Results: Our data showed that the skin of C3H mice with UVB-irradiated markedly decreased the collagen levels compared to the control. Moreover, pretreatment of 3% and 5% AH-8 ampoules on UVB irradiation increased collagen production. Furthermore, the elastin production was decreased in the UVB-irradiated group compared to the control and the elastin level in the skin of C3H mice was similar in both pretreated with 5% AH-8 on the UVB irradiation and control groups.Conclusions: This study has proven that HA-8 ampoules had a high capability of improving elasticity when compared to vehicle ampoule-containing ginkgo leaf and green tea extracts. Moreover, this study revealed the efficacy of AH-8 for increasing skin elasticity in terms of a cosmetic active ingredient.