Peptides are compounds formed by linking α-amino acids by peptide bonds, and are intermediate products of proteolysis. They are widely found in nature and perform a variety of physiological functions in living organisms. Tetrapeptide is a compound formed by the dehydration and condensation of four amino acid molecules, while acetyl tetrapeptide is a biomimetic peptide designed by mimicking the structure and function of the body's natural peptides. In this article, we will discuss the biological activity of several representative acetyl tetrapeptides and their application value in anti-aging and hair health.
Structural characteristics of acetyl tetrapeptide
The core structure of acetyl tetrapeptide consists of four amino acids, often with acetyl modifications to enhance its stability and biocompatibility. The introduction of acetyl groups not only improves the lipophilicity of the peptide, but also enhances its ability to penetrate the skin barrier, making it more effective in topical applications. The biomimetic properties of acetyl tetrapeptide allow it to bind to specific receptors in the human body, mimicking the biological functions of natural peptides, which paves the way for its application in the field of skin care and hair care.
Biological activity of acetyl tetrapeptide
Acetyl tetrapeptide has a variety of biological activities, mainly including anti-aging, eye care, and promoting hair health.
As we age, the elasticity and firmness of the skin gradually decreases, and the eye area is especially prone to signs of aging, such as eye bags and dark circles. Acetyl tetrapeptide fights free radical damage, inhibits glycosylation, prevents protein cross-linking, and ultimately improves skin elasticity and radiance by inhibiting angiotensin-converting enzyme (ACE), improving ocular microcirculation, increasing superoxide dismutase (SOD) activity.
Acetyl tetrapeptide-2 is a biomimetic of cell maturation factors produced by the thymus. Oxytocin acts locally on keratinocytes to induce intracellular synthesis of paracrine and auto secretory mediators. Oxytocin then stimulates keratinocytes to produce GM-CSF. This cytokine not only stimulates keratinocyte turnover, but also stimulates Langerhans cell maturation, as well as improves epidermal characteristics and stimulates the cutaneous immune system. It strengthens the skin's own defenses and helps to regenerate the epidermis.
Among them, acetyl tetrapeptide-5 is particularly good in eye care. Bad lifestyle habits such as staying up late for a long time can lead to increased pressure in the eyes, triggering a slowdown in ocular lymphatic circulation and increased capillary permeability, which ultimately leads to edema and the formation of dark circles. Acetyl tetrapeptide-5 reduces the production of angiotensin II by inhibiting ACE, thereby reducing capillary permeability, reducing fluid penetration into the tissues around the eye, and effectively alleviating edema.
Another commonly used acetyl tetrapeptide-9 optimizes the function of collagen fibers by regulating the activity of fibroblasts. The peptide promotes the synthesis of collagen and lumican by binding to specific receptors on fibroblast membranes, thereby improving the skin's regenerative capacity and fibrous structure. This mechanism of acetyl tetrapeptide-9 makes it an important ingredient in anti-aging skincare products, helping to restore the skin's youthful look and feel.
Acetyl Tetrapeptide-11 helps to rejuvenate aging skin by improving skin elasticity, firmness, and adhesion of the epidermis, resulting in a more radiant and even skin tone. These properties make acetyl tetrapeptide-11 an important application prospect in anti-aging skin care products.
Acetyl tetrapeptide 17 is a potent peptide that promotes collagen production. Acetyl tetrapeptide-17 stimulates the production of collagen, elastin, and other extracellular matrix proteins, as well as stimulation of fiber production. It is used in products such as anti-wrinkle, anti-aging, elasticity, and eye contour.
Fig.1 Structural formula of several acetyl tetrapeptides with anti-aging and eye protection functions.
Hair health problems, such as hair loss and thinning hair, are often accompanied by aging and changes in the environment. Acetyl Tetrapeptide-3 is a biomimetic peptide composed of four amino acids that mimics the action of natural peptides in the human body to promote healthy hair. It enhances the structural stability of hair follicles and promotes hair fixation and growth by accelerating the synthesis of extracellular matrix proteins such as laminin, collagen III and VII.
Acetyltetrapeptide-3 can directly act on the tissues around the hair follicle, expand the volume and length of the hair follicle, repair the epidermis and dermal connection tissue, and effectively maintain the normal cycle of the hair follicle. This mechanism not only helps to reduce hair loss due to aging, but also stimulates the growth of new hair, resulting in thicker and healthier hair and eyebrows.
Fig.2 Chemical structure of Acetyltetrapeptide-3.
Table 1 Acetyl tetrapeptides at Creative Peptides.
Source of acetyl tetrapeptide
Chemical synthesis: Acetyl tetrapeptides are typically chemically synthesized by solid-phase peptide synthesis (SPPS) technology. In this process, a tetrapeptide chain is synthesized through a series of amino acid coupling reactions, and an acetyl group is introduced at a specific position to form an acetyl tetrapeptide.
Degradation of native proteins: Acetyl tetrapeptide can be obtained by degradation of native proteins or enzymatic hydrolysis processes. In this case, the protein is cleaved into smaller peptides by enzymes, some of which may contain acetyl modifications.
Biosynthesis: In some cases, organisms can produce acetylated tetrapeptides through a post-translational modification process. These peptides may be secreted or released during specific biological processes.
Synthesis of acetyl tetrapeptides
Acetyl tetrapeptide is usually synthesized using solid phase peptide synthesis (SPPS) technology. In this method, the first Fmoc-protected amino acid is covalently linked to the solid support through its carboxyl terminus using an insoluble resin with functional groups as a solid support. Under the action of piperidine, the Fmoc protecting group of the amino group is removed, and then the next Fmoc amino acid is activated by a condensation agent (such as DIC/HOBT or DCC/NHS) to react with the amino acid on the solid phase support to form a new peptide bond.
This process is repeated until the desired peptide chain length is obtained. After the peptide chain is synthesized, the covalent bond between the peptide chain and the solid support is severed using the lysate to obtain a free acetyl tetrapeptide. Finally, the synthesized peptides were separated and purified by high-pressure preparative liquid chromatography (HPLC), impurities were removed to achieve the specified purity requirements, and the finished peptides could be obtained after freeze-drying.
Summary
As a multifunctional biomimetic peptide, acetyl tetrapeptide has shown great potential in the field of skin care and hair care due to its unique structure and wide range of biological activities. With the development of science and technology, the in-depth study of acetyl tetrapeptide will further reveal more of its biological functions and promote its wide application in the fields of beauty, health care and therapy. Through the scientific and rational use of acetyl tetrapeptide, we are expected to develop more safe and effective anti-aging and hair health products in the future, and contribute more to human health and beauty.
Reference
- Resende, Diana ISP, et al., Usage of synthetic peptides in cosmetics for sensitive skin. Pharmaceuticals 14.8 (2021): 702.
