Oligopeptides
Peptides or oligopeptides are the body’s own protein building blocks that give our cells the signal to regenerate the skin, but also fulfil other functions in the human body.
Peptides are characterised by the linkage of 2 or more amino acids, which are usually present as linear, occasionally also ring-shaped chain molecules. Amino acids are linked by a so-called peptide bond, i.e., via the carboxyl group of one amino acid with the α-amino group of the other amino acid under water splitting. The number of amino acids that can exist as a peptide runs into the thousands (there is no sharp delineation of peptide nomenclature, generally oligopeptides = 2-9, polypeptides = 10-100 and macropeptides have over 100 amino acids).
For example, they have antibacterial, antibiotic, or anti-inflammatory effects. Other peptides, in turn, appear in the form of hormones: Oxytocin and insulin are particularly well known in this context. Peptides can also act as poisons or are components of poisons, e.g., bee venom and snake venom. Taste peptides, such as sweet peptides (aspartame) or bitter peptides are also important. In cosmetics, oligopeptides or polypeptides are considered a wonder weapon against wrinkles and other signs of ageing of the skin, because they serve as a kind of signaller and cause our body to stimulate and improve certain physiological functions such as cell vitality, growth, and skin renewal. Several clinical studies have now confirmed the effectiveness of these substances.
Oligopeptides: Good for skin
The fact that peptides not only serve medical purposes but also have a highly efficient cosmetic effect was discovered rather by chance: namely during various studies on wound healing. From the enormous range of oligopeptides or polypeptides, some substances stand out particularly clearly. On the one hand, there are the argirelines (INCI designation: acetyl hexapeptides-3).
They are said to have a Botox-like effect because they are supposed to be able to inhibit the contraction of the facial muscles. But these peptides are not injected under the skin like Botox, but applied to the skin as ingredients in creams. Nevertheless, scientists found that argireline can reduce wrinkle depth by up to 30 percent. The peptides palmitoyl pentapeptide-4 also lead to a reduction in wrinkle depth or wrinkle width.
The peptides with the difficult name Dipeptide Diaminobutyroyl Benzylamide Diacetate have a similar effect, but at the same time they are able to make the skin supple and soft. Glutathione, a tripeptide that also belongs to the group of peptides, is used in skin care as an effective radical scavenger. The substance is involved in redox processes in the body. The so-called hexapeptides also alleviate stubborn expression lines. Basically, the most important peptides help to stimulate collagen production in the skin and promote skin elasticity. Some substances also have strong anti-inflammatory properties.
But these are by no means all the benefits. Oligopeptides and polypeptides are also very well tolerated and suitable for all skin types. By using preparations containing peptides, the natural skin barrier is not impaired but even strengthened. Those who regularly use appropriate cosmetic products usually look significantly younger and fresher after some time.
Cosmetic products such as anti-ageing creams containing peptides are primarily aimed at more mature skin from the age of about 35 to 40. Provided they are high-quality preparations, they are very effective, but only temporarily. This means that after discontinuation, the skin returns to its original condition after a certain time. Regular and continuous use is therefore strongly recommended. However, this is already the only disadvantage that cosmetics containing peptides have.
Peptides for hair care
Moreover, peptides can even stimulate hair growth. However, this only applies to certain substances: The peptides contained in the thymus gland are able to neutralise or normalise disorders of the hair follicle. Special preparations containing thymus peptides support the formation of new hair cells and prolong the growth phase of the hair. And what’s more: on bald patches, which, however, must not be more than three years old, these peptides can revive hair growth. Again, several clinical studies have confirmed their effectiveness.
Oligopeptides: the effect in cosmetics
Scientifically speaking, oligopeptides or polypeptides are parts or fragments of proteins. They differ from classical proteins only in the number of amino acids they contain. The more amino acids the molecule contains, the higher the probability that these are no longer peptides but proteins.
In order to be used in cosmetic products, peptides have to be produced artificially. If necessary, they can even be modified in their chemical composition. Peptides are still relatively new in the world of cosmetics. Long-term studies are not yet sufficiently available, yet it is considered proven that the highly effective substances actually act like a kind of fountain of youth. Ideally, oligopeptides or polypeptides are combined with other valuable ingredients in cosmetics. Together with vitamins such as A, C, E or pro-vitamin B5, they stimulate the naturally slowed regeneration of mature skin. Here are some examples of how peptides are used in cosmetics:
- Peptides with improved effect on collagen synthesis, e.g., palmitoyl pentapeptide.
- Peptides with effect on the neuromuscular synapses of the mimic wrinkles, Botox-like effect, well known representative is the acetyl hexapeptide (Argireline)
- Peptides with hormonal effects = cytokines and growth factors such as fibroblast growth factor (FGF). They are signalling molecules that control many biological processes.
- Non-specific oligopeptides such as soy oligopeptides and hydrolysed milk proteins. These oligopeptides are broken down in the skin and the resulting free amino acids support various skin functions.
- Aquaporins are also being mentioned more and more frequently. These are proteins that allow water to pass through cell membranes and thus enable moisturisation in deeper skin layers.
Conclusion: Peptides in cosmetics are more than just a passing trend
Cosmetic products with oligopeptides or polypeptides are currently flooding the market. However, this is by no means a temporary trend or a fad, but highly efficient substances that offer excellent tolerability. With regular use, high-quality and, if possible, certified preparations with peptides ensure that skin and hair remain healthy and age-related phenomena are alleviated or prevented. It can be assumed that in the future, research will be able to show further successes in the exploration of oligopeptides or polypeptides. In principle, the use of peptides in skin and hair care can therefore also be seen as clearly positive, especially since no undesirable side effects have been proven so far.
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