What are oligopeptides?
Oligopeptides, usually refer to short-chain polypeptides formed by the linkage of 2 to 20 amino acids through peptide bonds. These short peptides have important biological activities in vitro and in vivo, are widely found in natural proteins, and can also be obtained by artificial synthesis. Oligopeptides have a small molecular weight and a simple structure, but due to their flexible molecular configurations, they have a variety of functions and applications. Oligopeptides have gradually become a hot spot in research and application due to their good permeability and biological activity in cosmetics, medicine and biological research.
Oligopeptide vs peptide
The main difference between oligopeptides and polypeptides is the number of amino acids. Peptides are usually defined as peptide chains consisting of 10 to 50 amino acids, while peptide chains with more than 50 amino acids are usually classified as proteins. Due to their short chain length, oligopeptides are able to penetrate the skin barrier more easily and perform a variety of biological functions in and out of the body. Compared with peptides, oligopeptides are easier to synthesize and modify, and have better stability and absorption in skin care products.
Palmitoyl oligopeptide
Palmitoyl oligopeptide is a fatty acid-modified oligopeptide with good skin penetration and long-lasting moisturizing effect. It stimulates the synthesis of collagen and hyaluronic acid, strengthens the skin barrier function, reduces the appearance of fine lines and wrinkles, and is commonly used in anti-aging skincare products.
RH-Oligopeptide
Rh oligopeptide is a short-chain peptide produced by genetic recombinant technology, which has the effect of promoting cell growth and repairing the skin barrier. Taking rh oligopeptide-1 (rh EGF) as an example, it mimics the function of epidermal growth factor (EGF), which can stimulate skin cell proliferation, enhance skin repair ability, and effectively improve skin elasticity and radiance, and is often used in skin care products.
Examples of oligopeptides
Oligopeptide-1
Oligopeptide-1 is a peptide composed of glycine, histidine and lysine, which is a small molecule active peptide with a molecular weight of less than 1,000 Da, and its volume is 3,000 times smaller than that of bacteria, which is very easily absorbed by the skin. Oligopeptide-1 is a popular skin care ingredient recently, which can play a good role in repairing dry, yellowish and sensitive skin, and water and oil imbalance. Oligopeptide-1 is a natural built-in dermal repair modifier. It is the amino acid sequence in the ECM protein, type I collagen, which can be released by proteases at the wound site, which can activate and regulate the skin repair process. At the same time, oligopeptide-1 can activate the expression of integrins and increase the stemness and proliferative potential of keratinocytes.
SH-Oligopeptide-1
SH-Oligopeptide 1, or epidermal growth factor (EGF), is a synthetic analog of human polypeptide EGF. SH-Oligopeptide 1 is an active protein present in the human body, composed of 53 amino acids, and its relative molecular weight is about 6,200 Da. SH-Oligopeptide 1 was first discovered in 1962 by United States scientist Dr. Stanley Cohen from the visceral and exocrine glands of animals, and Dr. Cohen won the 1986 Nobel Prize in Physiology or Medicine for his discovery of EGF. With the deepening of the research on sh-oligopeptide 1, it was found that sh-oligopeptide 1 can promote the synthesis of DNA and RNA in the process of skin wound tissue repair, accelerate the generation of wound granulation tissue and the proliferation of epithelial cells, thereby shortening the wound healing time and improving the quality of wound repair. Therefore, sh-oligopeptide 1 has a wide range of applications in medicine.
Fig.1 Amino acid sequence of SH-Oligopeptide-1 (EGF). (Bavaro Teodora, et al., 2021)
Table 1 Oligopeptides at Creative Peptides.
SH-Oligopeptide-78
Based on the structure of keratin and keratin-related proteins, sh-Oligopeptide-78 is a synthetic peptide sequence similar to keratin that does not depend on hydrophobic binding domains and/or carbohydrates, but on disulfide bonds. SH-Oligopeptide-78 contains sulfur-containing amino acids, specifically cysteine, which interacts with the hair and allows the formation of disulfide bonds, which stabilize keratin fibers and protect hair fibers.
Oligopeptide 104
Oligopeptide-104 is an oligopeptide that promotes hair growth, which prolongs the hair growth cycle by activating hair follicle stem cells, thereby preventing hair loss and promoting the growth of new hair. This oligopeptide is often used in hair growth products.
Oligopeptide 20
Oligopeptide-20 is mainly used in anti-aging and whitening products. It inhibits the activity of tyrosinase, thereby reducing the production of melanin and brightening the skin. At the same time, oligopeptide-20 can also promote collagen production, improving skin elasticity and delicacy.
Oligopeptide benefits
Oligopeptides have significant benefits in the field of biomedicine and beauty and skin care due to their diverse functions and efficient activities. First of all, oligopeptides have a smaller molecular weight and are better able to penetrate the skin barrier and act directly on the dermis to exert their biological effects. Secondly, oligopeptides have high biological stability and are not easily broken down by enzymes in the skin, so they can have a long-lasting effect. In addition, oligopeptides have anti-inflammatory, antioxidant, and promote cell repair and regeneration, which can significantly improve skin condition and delay the aging process.
Oligopeptide function
Oligopeptide for skin
Oligopeptides have a wide range of applications in skin care. They stimulate collagen production, promote cell renewal and repair, and improve skin elasticity and radiance. Oligopeptides are often added to anti-aging skincare products to reduce fine lines and wrinkles and increase skin firmness. In addition, certain oligopeptides also have anti-inflammatory and antibacterial effects, which can be used to care for sensitive or problematic skin.
Oligopeptides for lips
Oligopeptides are also gaining traction in lip care products. The skin on the lips is thin and susceptible to environmental irritants and moisture loss, leading to chapped and aging. Oligopeptides are able to promote the hydration of the lip skin, increasing its elasticity and fullness, while reducing the formation of lip lines for a smoother and more refined lip area.
Oligopeptide for hair
In hair care, oligopeptides are widely used in products that prevent hair loss and promote hair quality improvement. Oligopeptides can activate hair follicle cells, prolong the hair growth cycle, and reduce hair loss. In addition, oligopeptides can also improve the health of the scalp, reduce the production of dandruff, and make hair thicker and shinier.
Oligopeptides can be obtained by both chemical synthesis and biosynthesis.
Chemical synthesis
Chemical synthesis is mainly carried out by solid-phase peptide synthesis (SPPS), in which amino acids are gradually linked to form oligopeptide chains. This method allows for precise control of the sequence and length of oligopeptides, making it suitable for large-scale production.
Introduction of protective groups: The α-amino and side-chain functional groups of amino acids need to be protected to prevent unintended chemical reactions during the reaction. Protecting groups (e.g., Boc, Fmoc, etc.) are commonly used to protect amino acids.
Activation: The protected amino acids need to be activated to make them reactive in order to condense with the next amino acid. Commonly used activation reagents include bis(diphenyl) carbonate (DCC) and 1-hydroxylic acid (HOBt).
Condensation reaction: The activated amino acid undergoes a condensation reaction with the next protected amino acid to form a new peptide bond. Reaction conditions can be in solution or solid phase synthesis. In solution-phase synthesis, the reaction is usually carried out in an organic solvent with the addition of an appropriate amount of alkali catalyst. In solid-phase synthesis, amino acids are immobilized on solid-phase support, and the reaction takes place on the solid-phase support.
Removal of protecting groups: After the synthesis of peptides is completed, it is necessary to remove the protecting groups and restore the free functional groups of amino acids.
Purification and analysis: Synthetic peptides need to be purified, and chromatographic techniques (such as reverse phase chromatography, gel filtration, etc.) are usually used to separate and purify peptides. After separation and purification, mass spectrometry, nuclear magnetic resonance, and other methods can be used for structural analysis and confirmation.
Biosynthesis
Biosynthesis, on the other hand, uses microorganisms or biological enzymes to generate oligopeptides, which has the advantages of low cost and environmental friendliness, but has certain challenges in sequence control and purity.
Summary
As an important bioactive substance, oligopeptides have a wide range of application prospects in medicine, cosmetics and biological research due to their diverse functions and efficient activities. As technology advances, more oligopeptides with specific functions will be developed, providing more solutions for skin care, hair care, and overall health.
Reference
- Bavaro, Teodora, et al., Design of epidermal growth factor immobilization on 3D biocompatible scaffolds to promote tissue repair and regeneration. Scientific reports 11.1 (2021): 2629.
