Peptide regulation of enzyme activity is the main link in the management of aging

Fortunately, technological progress in aesthetic medicine has led to scientists reaching the heights of their scientific creativity and creating unique substances that can completely regulate cell function, affecting all links in the pathogenesis of aging. The name of these substances is biomimetic peptides.

More recently, in the cosmetology world there was a belief that it is enough to introduce hyaluronic acid (HA), vitamins, and minerals into the skin - and everything will fall into place: fibroblasts will begin to divide, the processes of collagen and elastin synthesis will start, and the amount of endogenous HA will increase. But the emergence of biomimetic peptides has somewhat changed the view of geroprotective programs in cosmetology.

Biomimetic peptides are small compounds consisting of a specific sequence of amino acids and have maximum selectivity towards the cell. Their selectivity is ensured by the receptor mechanism of action. For each peptide introduced into the skin from the outside, there is a specific receptor on the cell membrane. The peptide-receptor interaction leads to the activation of successive biochemical reactions, as a result of which one or another therapeutic effect is achieved.

The selectivity of peptides ensures the absence of addiction and ensures maximum safety for the skin and the body as a whole. The method of obtaining peptides is also important, since their activity and effectiveness will depend on this. Today there are two methods:

• hydrolysis;
• biosynthesis.

The essence of hydrolysis is the breakdown of large proteins into small peptides, but in this case the effectiveness of such compounds will be very insignificant.

Unlike hydrolyzed peptides, biosynthetic ones are obtained from a specific set of amino acids. Depending on which amino acids are included in the peptide, its specificity will be determined. Biomimetic peptides obtained by biosynthesis have maximum efficiency, since each peptide has strict selectivity for receptors on the cell membrane. Consequently, the use of drugs based on biosynthetic peptides makes it possible to most accurately influence all links in the pathogenesis of aging, as well as solve narrowly targeted problems.

Depending on the direction of action, biomimetic peptides can be divided into three groups:

• inhibitors - a class of peptides that block enzymes that lead to destructive changes in the components of the extracellular matrix;
• stimulants - peptide complexes that trigger the processes of cell proliferation (fibroblasts, keratinocytes), stimulation of the synthesis of collagen, elastin, fibronectin and HA;
• muscle relaxants - peptides with botulinum-like effects.

It is known that, starting from 25-27 years of age, structural changes in cells and intercellular substance occur in the skin. There is an active decrease in the amount of glycosaminoglycans, the main of which is HA, “correct” collagen (intact fibers are replaced by fragmented ones) and elastin. There are quite a lot of factors influencing all these processes: excessive insolation; stress; taking medications; genetic predisposition; hormonal changes. Any of the listed reasons leads to the fact that the balance between the processes of synthesis and breakdown of the main structures of the intercellular matrix is disturbed in the body. It also accelerates processes leading to premature cell death.

The destruction of HA and the fiber framework of the skin is caused by the work of hyaluronidase and enzymes from the group of matrix mellalloproteinases (MMPs).

Matrix metalloproteinases are divided into several subgroups, depending on substrate specificity (substrate is the substance that the enzyme acts on):

• collagenase;
• gelatinases;
• stromelysins;
• membrane-bound MMPs;
• unclassified.

Within cosmetology, the class of collagenases and gelatinases, namely matrix metalloproteinase type 2 (MMP2), is of greatest interest. MMP2 ensures the degradation of collagen types I, IV, V, VII, X, XI, fibronectin, elastin and laminin. The amount of MMP2 may vary depending on the status of the endocrine system. For example, with a sufficient level of female sex hormones, the activity of MMP2 is inhibited, excessive activation of the destruction of extracellular matrix components does not occur, therefore, involutional processes do not enter the active phase.

But with the onset of menopause in women, the level of MMP2 shifts towards an increase, since hormonal changes occur very intensively, and it is during this period that age-related changes in the skin actively manifest themselves. Another condition in which overproduction of MMP2 is observed is hypothyroidism. Reduced synthesis of hormones T3, T4 leads to increased synthesis of MMPs and, as a result, the aging process accelerates, skin turgor and elasticity decrease. And the implementation of injection geroprotective programs gives only short-term results.

Hyaluronidase is an enzyme that destroys endogenous hyaluronic acid. The degree of hyaluronidase activity is different in all people, and it is not possible to determine the exact age range. In addition, there are so-called risk groups - patients with genetically dry skin and people who abuse tanning. For hyaluronidase, UV radiation is a kind of catalyst for enzyme activity. As a result, the rate of degradation of hyaluronic acid increases by almost 50%, the balance shifts towards destruction, therefore, the synthesis of new HA will depend on the functional activity of fibroblasts and, in the case of an initially reduced potential of the main cells of the dermis, the skin aging process is automatically potentiated. Therefore, in the summer, it is especially important to use drugs that block this enzyme and increase the antioxidant status of the skin. If antioxidant protection is neglected, free radical reactions intensify, leading to cell damage and disturbances in protein synthesis processes.

Thus, when carrying out anti-age therapy, it is not enough to just stimulate the renewal of the extracellular matrix; it is necessary to inhibit its destruction, ensuring a balance between synthesis and destruction.

First published: Cosmetologist No. 3, 2016