Cosmetic Peptides

Cosmetic peptides are short sequences of amino acids which serve as building blocks of proteins. Their source can be natural as well as synthetic. Irrespective of the origin, peptides are biologically active and mediate various physiological effects, such as regulating metabolism, developing muscles, improving cognitive function, and increasing sex drive.

Peptides function as interesting cosmeceutical ingredients

Peptides are often a part of the active ingredients of various beauty products. Hence their function, chemical stability, and bioavailability are under stringent scrutiny. Novel physical and chemical techniques are under evaluation to improve the efficacy of cosmetic peptides.

The stability and enhanced bioavailability of the peptides in medication and cosmetics are of significant concern. The scientific community has coined the term “cosmeceuticals” to refer to the group of peptides that find increasing applications as ingredients in various cosmetic products. Researchers are actively working on means to improve the bioavailability and stability of such peptides. Interestingly, there are more than two hundred different research articles on various peptides, but only a few of them focus on the issue of their active permeation into the body.

Peptides have long been used as effective carriers for larger molecules in the body. Interestingly, now they are actively used in cosmetics to improve various cellular processes like skin cell rejuvenation and growth of hair follicles. RTTKS is one of the well-known molecules. However, there is minimal scientific data about the testing of such peptides in the cosmetic field. Many of the peptides used in cosmeceutical formulations have been pharmacologically tested. However, they lack relevant and sufficient information about their bioavailability and stability. These data are especially relevant since the formulations are directly applied ectopically on the human skin. Various pharmacologically proven methods, such as transdermal administration, have been used to enhance the bioavailability of peptide formulations by the beauty industry.

Means to improve the stability and skin pervasion of peptides

Scientific reviews have highlighted two essential methods of improving the skin pervasion of peptides. The first route is through the Stratum corneum, and the second one is via increased peptide stability for dermal enzymes. As per research findings, either physical or chemical enhancers can be used to enhance peptide bioavailability. Physical enhancers include ultrasonic waves, microneedles, and low electric current. Free fatty acids, alcohols, or surfactants are among the chemical enhancers used. There are additional chemicals such as hydrogels, liposomes, microemulsions, nanostructured lipids, and polymer-based techniques.
Both the physical and chemical methods were developed to enhance transdermal delivery and the bioavailability of the molecules in general. They mediate their function by one of the three mechanisms:

1. Disturbance of Stratum corneum lipid layer.
2. Co-enhancer or solvent-mediated improved drug partitioning into Stratum corneum layer.
3. Inter-cellular protein interference.

Future of active peptide: microneedle innovation under the spotlight

The microneedle method has been considered an innovative technique for intradermal delivery of peptide formulations. It is used to puncture the external skin layers and allow permeation and absorption of the active ingredients. Microneedles help to prick the upper layers of skin subaerially and are very helpful in the delivery of hydrophilic molecules. Microneedle rollers, as well as 3D printed microneedle eye patches, are also available. These have been tested on mice and human skin with significant results. Self-dissolving microneedles have also shown beneficial outcomes.

Chemical degradation of active peptides poses a major challenge.

As per researchers, peptide stability in cosmetic formulations would continue to be a challenge. This is due to a significant increase in peptide use in the formulations and specific skin permeability and metabolic improvement objectives. Chemical degradation of peptides occurs due to the abundance of proteases on the skin, which target and break down the peptides. Hence the bioavailability of the peptides gets compromised. Often covalent bond-mediated synthetic modifications of peptides improve their skin permeability. However, these modifications make them more prone to dermal protease-mediated degradation. Interestingly, new chemical changes have been useful in improving the dermal stability of the molecules. A few noted ones include peptide backbone modifications, the use of cyclic peptides, ascorbic acid conjugations, and peptide conjugations.

Thus, with increased peptides applications in the beauty industry, novel physical and chemical methods have been developed to improve their dermal stability. There are continuous developments in these methods, which provide impetus to novel and innovative technological solutions to improve products.

Disclaimer: The products mentioned are not for human or animal consumption. All the information shared in this article is for educational purposes only.