Topical treatment with a cathepsin G inhibitor, β-keto-phosphonic acid, blocks ultraviolet irradiation-induced basement membrane damage in hairless mouse skin

Palmitoyl‑RGD promotes the expression of dermal‑epidermal junction components in HaCaT cells

With age, the dermal‑epidermal junction (DEJ) becomes thinner and production of its protein components decreases; this may be associated with increased fragility and wrinkling of skin. Topical treatment with palmitoyl‑Arg‑Gly‑Asp (PAL‑RGD) improves facial wrinkles, skin elasticity and dermal density in humans. In the present study, the effect of PAL‑RGD on expression of DEJ components, such as laminin and collagen, was assessed. Human HaCaT keratinocytes were treated with PAL‑RGD. The protein expression levels of laminin‑332, collagen IV and collagen XVII were examined by western blotting. Reverse transcription-quantitative PCR was used to analyze laminin subunit (LAM)A3, LAMB3, LAMC2, collagen type IV α 1 chain (COL4A1) and COL17A1 mRNA expression levels. Western blot analysis showed that the expression levels of proteins comprising the DEJ, including laminin α3, β3 and γ2 and collagen IV and XVII demonstrated a significant dose‑dependent increase following PAL‑RGD treatment. Furthermore, PAL‑RGD treatment significantly enhanced LAMA3, LAMB3, LAMC2, COL4A1 and COL17A1 mRNA expression levels. PAL‑RGD may enhance the DEJ by inducing the expression of laminin‑332, collagen IV and collagen XVII.