Abstract:

In this study, three cosmetic ingredients with reported anti-glycation activity—carnosine, chlorogenic acid, and curcumin—were evaluated across glycation models representing different stages of glycation-related damage. Three stage-specific glycation injury models were established in HFF-1 human dermal fibroblasts via stimulation with a glucose solution （early stage）, a glyoxal solution （middle stage）, and an advanced glycation end products （AGEs） solution （late stage）, respectively. Intracellular reactive oxygen species （ROS） levels were quantified using a fluorescent probe assay by measuring mean fluorescence intensity, while intracellular Nε-carboxymethyllysine （CML） content and elastin （ELN） levels in the cell culture supernatant were determined by ELISA. The results show that, in terms of intracellular free-radical scavenging capacity, curcumin exhibits the highest potency, followed by chlorogenic acid and carnosine. With respect to the inhibition of CML formation, chlorogenic acid is most effective in the early-stage model, followed by carnosine and curcumin; in the middle- and late-stage models, curcumin shows the strongest inhibitory effect, followed by carnosine and chlorogenic acid. Regarding the protection of ELN in the culture supernatant, carnosine exhibits the greatest protective effect, while chlorogenic acid and curcumin showed similar effect. Overall, these findings indicate that the anti-glycation effects of carnosine, chlorogenic acid, and curcumin differ in a stage-dependent manner. In addition, the three stage-specific glycation damage models effectively discriminate the efficacy of the tested ingredients, thereby providing a useful reference for subsequent efficacy evaluations.

Key words: glycation damage, anti-glycation, in vitro cell model, efficacy