The research, conducted by L’Oréal researchers in China, Japan and the US, suggested that the combination of acetyl hexapeptide-8, dipeptide diaminobutyroyl benzylamide diacetate, and gluconolactone offered a potent skin care solution.
The study found that the formulation effectively targeted the structural decline of the skin while simultaneously relaxing the muscle contractions that led to expression lines.
Skin ageing is a complex process driven by both genetics and external factors like UV radiation.
While many anti-ageing products in the market focus solely on static wrinkles (the lines that remain visible while the face is at rest), this study also measured the impact on dynamic wrinkles, which appear during facial expressions such as smiling.
The researchers tested a serum, referred to as Formula 1, which featured a synergistic blend of five active ingredients — acetyl hexapeptide-8, dipeptide diaminobutyroyl benzylamide diacetate, gluconolactone, niacinamide, and laminaria extract.
“By inhibiting the assembly of the SNARE complex — a group of proteins pivotal in the formation of wrinkles — acetyl hexapeptide-8 prevents the repetitive contraction of facial expression muscles,” the study’s authors noted.
They added that dipeptide diaminobutyroyl benzylamide diacetate worked in a similar way as botulinum toxin by blocking signal transduction to relax the treated area.
Significant boosts in skin biomarkers
An ex vivo study using skin explants to measure changes in structural proteins vital for skin integrity showed that the serum significantly increased the levels of anti-ageing biomarkers.
Specifically, the formulation boosted type I collagen by 289% and type IV collagen by 109%, compared to a negative control.
The study also recorded a 122% increase in elastic fibres and a 252% increase in elastin, which are critical for maintaining skin firmness and preventing sagging.
Clinical results show rapid improvement
Following the lab tests, two clinical trials were conducted with Chinese female participants to validate the serum’s performance in real-world conditions.
In the first study, 50 participants applied the serum twice daily. Dermatologists used clinical scoring and advanced imaging tools to track progress. The data revealed that significant improvements in static wrinkles were observed as early as the first week.
After 12 weeks of consistent use, the results were even more pronounced. Clinical scores for forehead wrinkles improved by 58%, while fine lines on the forehead saw a 69% improvement. Crow’s feet were reduced by 39%, and underneath eye wrinkles improved by 55%.
Instrumental measurements backed up these visual scores. Primos-lite data showed a 34% reduction in the number of crow’s feet and a 29% decrease in the count of forehead wrinkles.
Additionally, Ultrascan UC22 measurements indicated that dermal thickness increased by 12% over the 12-week period.
Tackling expression lines
The second clinical study focused specifically on dynamic wrinkles in 42 participants. Using high-speed cameras to capture faces during a smile, the researchers found that the serum significantly softened expression lines.
Under a full smile, clinical scoring for under-eye wrinkles decreased by 10%, nasolabial folds (smile lines) by 13%, and crow’s feet by 11%.
The researchers highlighted that the serum remained effective across different intensities of facial expression, from a neutral face to a maximum smile.
Beyond wrinkle reduction, the serum delivered broad improvements to overall skin texture and appearance.
After 12 weeks, dermatologists observed significant improvements across several categories, namely skin smoothness (30%), skin radiance (27%), skin pore appearance (43%), skin elasticity (33%), and skin firmness (36%).
The participants’ self-assessments mirrored these clinical findings. At the end of the study, the participants reported that their skin felt more rejuvenated and vital. They also praised the serum’s “cosmeticity”, noting that it was lightweight, non-greasy, and worked well under makeup.
A synergistic approach
The authors suggested that the combination of the five ingredients performed better than the individual components or smaller peptide pairings. For instance, the blend was more effective at increasing type I and IV collagen than a combination containing only the two primary peptides.
“These results suggest a possible synergistic interaction among the five active ingredients, enhancing collagen synthesis, improving elasticity and contributing to wrinkle reduction while maintaining an excellent safety profile,” they concluded.
While the study was limited to a Chinese population and lacked a separate control group, the researchers believe the robust data from ex vivo and clinical testing provides a strong scientific foundation for this formulation in the competitive anti-ageing market.
Source: International Journal of Cosmetic Science
“The effect of a serum containing acetyl hexapeptide-8, dipeptide diaminobutyroyl benzylamide diacetate and gluconolactone on skin biomarkers, wrinkles and skin texture: Ex vivo and clinical studies”
https://doi.org/10.1111/ics.70087
Authors: Zhu Mingjie, et al
