Research & Bioactivity
Acetyl Hexapeptide-3, also known by the trade name Argireline, is a synthetic hexapeptide that researchers have studied extensively in relation to neuromuscular signaling and skin biology. Studies have examined its interaction with components of the SNARE protein complex, which plays a role in neurotransmitter release, with in vitro research investigating how the peptide may interfere with acetylcholine vesicle docking at neuromuscular junctions. Research has also investigated its copper(II) ion chelating properties, with laboratory studies using potentiometric titration and complementary analytical techniques to characterize how structural modifications to the peptide influence metal ion affinity. In vitro studies using human skin fibroblast models have examined Acetyl Hexapeptide-3 as part of cosmeceutical peptide combinations, exploring its potential role in modulating markers associated with oxidative stress and cellular senescence. Additionally, researchers have developed advanced skin spheroid models integrating sensory neurons to better evaluate how neuropeptide-based compounds like this one interact with neural components of skin tissue, acknowledging that conventional in vitro models have historically been limited in capturing such interactions.
Published Research
Development of a Sensory Neuron-Integrated Skin Spheroid Model for the Evaluation of Neuropeptide-Based Topical Delivery Systems.
Martin BA, Viegas J, Dalmolin LF, Santos ES, Vatanabe IP, et al. — 2025
The skin is a complex organ composed of multiple layers and diverse cell types, including keratinocytes, fibroblasts, adipocytes, and sensory neurons, which maintain its structural and functional integrity together. Conventional in vitro and ex vivo models help investigate drug permeation and selected biological effects. However, they are limited in replicating neural interactions critical for assessing the efficacy of neuropeptide-based therapies. To address this limitation, a sensory neuron-integrated skin spheroid (SS) model was established, incorporating key skin cell types and providing a rapid, adaptable, and physiologically relevant platform for screening the biological activity of topical delivery systems targeting neuronal pathways. The model's responsiveness was demonstrated using acetyl hexapeptide-3 (HEX-3), a neuropeptide that inhibits acetylcholine release. HEX-3 was internalized by spheroid cells, with preferential accumulation around sensory neurons, confirming targeted cellular uptake. In parallel, ex vivo human skin studies confirmed that HEX-3 can traverse the stratum corneum and accumulate in deeper layers. Treatment with this film enhanced skin hydration, reduced scaling, and improved the structural organization of the stratum corneum after 48 h. Functional assays using the SS model showed that HEX-3 treatment suppressed acetylcholine release, upregulated the antioxidant enzyme SOD2, and stimulated type I collagen synthesis. In aged skin samples, the application of HEX-3 significantly increased collagen levels. This effect was mirrored in the spheroid model, which reached collagen levels comparable to those of aged human skin upon treatment. These findings establish the SS model as a robust platform for evaluating the biological activity of neuropeptide-based topical therapies, offering valuable insights for developing advanced strategies for skin rejuvenation and repair.
Acetyl Dipeptide-31 Amide: A Novel Cosmetic Anti-Inflammatory Peptide That Demonstrates Anti-Aging, Firming, and Lifting Benefits.
Edison BL, Parsa R, Dufort M, Tierney NK, Green BA, et al. — 2025
BACKGROUND: There is continuous demand for safe, effective cosmetic ingredients to treat the signs of aging skin, including fine lines, wrinkles, brown spots, discoloration, laxity, and sagging. While there are a plethora of cosmeceutical peptides, few combine anti-aging and anti-inflammatory benefits with small size. METHODS: Preclinical and clinical studies evaluated the anti-inflammatory properties, anti-aging benefits, and tolerability of acetyl dipeptide-31 amide (AP31), a novel, small, anti-aging micropeptide, to understand its impact as a multifaceted, cosmetic, anti-aging, and anti-inflammaging ingredient. RESULTS: In vitro, AP31 statistically significantly reduced the release of inflammatory mediators interleukin (IL)-4, IL-6, IL-8, IL-17, and tumor necrosis factor alpha, and statistically significantly increased levels of dermal extracellular matrix components, ie, procollagen, elastin, decorin, fibronectin, and hyaluronic acid (all P<0.05 vs vehicle controls). Statistically significant increases in extracellular matrix biomarker levels were also seen in AP31-treated human skin explants (8 days). In human skin equivalents, AP31 favorably influenced cellular pathways known to contribute to skin aging. AP31 positively impacted genes involved in barrier function, skin hydration, skin plumping, and epidermal metabolism. Clinical evaluations of a finished product over 16 weeks demonstrated improvements in jawline sagging, global lift, nasolabial fold appearance, fine lines and wrinkles, smoothness, skin tone, and hyperpigmentation. Subject self-assessment of efficacy was consistent with the clinical grading. No statistically significant changes from baseline in tolerability assessments of edema, erythema, dryness, burning, stinging, itching, or tightness were reported. CONCLUSIONS: AP31 is a novel, multifunctional, non-irritating, cosmeceutical micropeptide that improves clinical signs of aging, lifts and contours facial skin, and reduces inflammation markers. J Drugs Dermatol. 2025;24(1):23-33. doi:10.36849/JDD.8786.
INDIVIDUAL ARTICLE: Real-World Clinical Experience With a Neuro-Peptide Serum in Combination With Botulinum Toxin Type-A Injections.
Lupin M, Bjerring P, Andriessen A, Chantrey J, Fabi SG, et al. — 2024
We evaluated real-life experiences of a topical neuro-peptide serum containing 2% acetyl hexapeptide-8, 2% dipeptide diaminobutyroyl, 5% polyhydroxy acids (PHA), 5% niacinamide, and 1% laminaria extract (topical neuro-peptide serum [TNP-serum]). The TNP-serum works synergistically by stimulating 9 key skin biomarkers to reduce wrinkles and produce a skin-brightening effect. Here, we highlight the real-life experiences of 5 dermatologists and 2 surgeons, using an integrated skincare regimen consisting of botulinum toxin type-A (BTX-A) injection in conjunction with twice daily TNP-serum. Real-world cases provide evidence for combination treatments that may be used in cosmetic dermatology to improve patient outcomes and satisfaction. TNP-serum appears to complement BTX-A injections to improve radiance, reduce fine lines, and reduce wrinkles in diverse patients. Incorporating TNP-serum into integrated skincare regimens may offer an additive effect to BTX-A injections and, ultimately, optimize patient results. J Drugs Dermatol. 2024;23:11(Suppl 2):s3-14.
Influence of the modification of the cosmetic peptide Argireline on the affinity toward copper(II) ions.
Wyrzykowski D, Wieczorek R, Kloska A, Errante F, Papini AM, et al. — 2024
Argireline (Ac-EEMQRR-NH ), a well-known neurotransmitter peptide with a potency similar to botulinum neurotoxins, reveals a proven affinity toward Cu(II) ions. We report herein Cu(II) chelating properties of three new Argireline derivatives, namely, AN4 (Ac-EAHRR-NH ), AN5 (Ac-EEHQRR-NH ), and AN6 (Ac-EAHQRK-NH ). Two complementary experimental techniques, i.e., potentiometric titration (PT) and isothermal titration calorimetry (ITC), have been employed to describe the acid-base properties of the investigated peptides as well as the thermodynamic parameters of the Cu(II) complex formation. Additionally, based on density functional theory (DFT) calculations, we propose the most likely structures of the resulting Cu-peptide complexes. Finally, the cytotoxicity of the free peptides and the corresponding Cu(II) complexes was estimated in human skin cells for their possible future cosmetic application. The biological results were subsequently compared with free Argireline, its Cu(II)-complexes, and the previously studied AN2 derivative (EAHQRR).
Protective and Anti-Aging Effects of 5 Cosmeceutical Peptide Mixtures on Hydrogen Peroxide-Induced Premature Senescence in Human Skin Fibroblasts.
Wu Y, Cao K, Zhang W, Zhang G, Zhou M — 2021
Skin aging usually leads to the excessive deterioration of the dermal extracellular matrix, loss of antimicrobial function, loss of skin barrier function, and a series of inflammatory processes. Bioactive peptides have been widely used in cosmetics due to their protective effects on skin and efficient absorption. Combination of different peptides may lead to synergistic or antagonistic effects, so different formulas need to be designed and tested properly. In this study, 5 functional cosmeceutical peptides were tested on their individual and mixed activities to detect a suitable anti-aging and protective formula from our experiments. After the individual activity test, the optimal concentration is 200 μg/mL of carnosine for the superoxide dismutase (SOD) activity, 200 μg/mL of GHK peptide for the hydroxyproline (HYP) content activity, 100 μg/mL of acetyl tetrapeptide-5 for the angiotensin-converting enzyme 1 activity, 400 μg/mL of hexapeptide-11 for the HYP content activity, and 400 μg/mL of acetyl hexapeptide-3 for the catecholamine content activity. According to the optimal concentration of these 5 cosmeceutical peptides, 6 formulations of peptide mixtures were designed and tested for their anti-aging activities and protective effects against hydrogen peroxide-induced premature senescence in human skin fibroblasts. One of the cosmeceutical peptide mixtures (carnosine + acetyl tetrapeptide-5 + hexapeptide-11 + acetyl hexapeptide-3) significantly reduced the intracellular malondialdehyde and hydroxyl free radical contents and increased the HYP and human elastin contents as well as the enzymatic activities of SOD and glutathione peroxidase. Our study suggests that this formula of cosmeceutical peptide mixtures could be a promising agent for use in anti-aging and protective cosmetics.