Potential of Tomato Seed Extract for Wrinkle Care through Human Neutrophil Elastase Inhibition: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Numerous cosmetic products claim to improve aging-induced wrinkles, and recent research has explored the potential of oral intake for wrinkle improvement. In our previous study, we investigated the effects of tomato seed extract (TSE), which contains lycoperoside H, on skin elasticity and its anti-inflammatory properties. The present study aimed to explore the anti-wrinkle effects of TSE through the inhibition of human neutrophil elastase (HNE), activated by inflammatory stimuli. The results indicated that TSE inhibits HNE (half maximal inhibitory concentration [IC₅₀]: 316 μg/mL), and that lycoperoside H contributes to this activity (IC₅₀: 37 mM). Additionally, several flavonoids found in TSE have been reported to exhibit HNE inhibitory effects. Based on these findings, we hypothesized that TSE supplementation could suppress excessive HNE activity in wrinkle-prone areas and potentially improve facial wrinkles. Therefore, we conducted a randomized, double-blind, placebo-controlled clinical trial with 45 healthy Japanese women (age range, 40-59 y) who had wrinkle grades of 3-5 around their eyes. The participants were randomly assigned to either a 200 mg/d TSE supplement (containing 1 mg of lycoperoside H) or a placebo for 12 wk. As a result, significant improvement in wrinkle grade was observed in the TSE group; however, improvements were also seen in the placebo group. Therefore, no significant differences in wrinkle reduction were found between the two groups. These findings suggest that the inhibition of HNE by TSE may have potential effects on the dermis, thereby offering new insights into the role of TSE in skin health.