Hyaluronic acid is a substance naturally produced by our body with the aim of hydrating and protecting the tissues.
Hyaluronic Acid: Chemical Structure and Functions
From the chemical point of view, hyaluronic acid is classified as a glycosaminoglycan. The molecule is in fact formed by the repetition of long sequences of two simple sugars, glycuronic acid and N-acetylglucosamine. These substances are both negatively charged and when joined together the strong repulsion gives rise to a linear, flexible and extremely polar molecule. The great solubility in aqueous environment is important to guarantee the hydration of the tissues while protecting them from excessive stresses and strains. At the same time the high affinity with other hyaluronic acid molecules and with the other components of the extracellular matrix allows the formation of a dense and intricate high molecular weight network.
Also present in many animals and in some types of bacteria hyaluronic acid represents one of the main components of connective tissue, in particular of its amorphous substance (or fundamental substance, a compact gel in which collagen and elastin fibers are immersed).
Discovered in the vitreous humor of the eye and used since the 70s until a few years ago this mucolpolysaccharide was extracted exclusively from animals and in particular from the cockscomb. Today, avian hyaluronic acid is combined with that extracted from particular bacteria. Modern production techniques allow the synthesis of different types of hyaluronic acid with different characteristics and fields of application.
Further reading:
Hyaluronic acid: effective also orally? Hyaluronic acid (sodium salt) in cosmetics Hyaluronic acid hydrolyzed in cosmetics Infiltration of hyaluronic acid Hyaluronic acid filler Hyaluronic acid creamHyaluronic Acid Functions
The particular chemical structure gives the hyaluronic acid numerous properties that make it particularly useful both in the medical and aesthetic fields. Its ability to bind water and other substances in fact gives rise to protective gels, particularly useful for the skin and joints.
By stimulating the formation of collagen and connective tissue, hyaluronic acid protects the body from viruses and bacteria, increases tissue plasticity and guarantees optimal skin hydration. It also has cicatricial and anti-inflammatory properties.
It is easily obtained in the laboratory and if we exclude isolated cases of hypersensitivity to the substance it is free of contraindications or side effects.
Wrinkles and Hyaluronic Acid
Hyaluronic acid is a fundamental component of the dermis. Thanks to its properties it gives the leather the classic characteristics of elasticity and softness. However, its concentration in the connective tissue of the skin tends to decrease with advancing age. If on the one hand this constant and considerable decrease is among the main responsible for skin aging on the other hand the injection of hyaluronic acid allows to reactivate mature skin stimulating cellular functionality and giving the skin the compactness and the lost lucidity.
For all these reasons this substance has been used successfully in the dermatological-aesthetic field for several years now.
In particular, the treatment based on collagen and hyaluronic acid is the basis of the so-called fillers, treatments used to fill and smooth facial wrinkles.
The preparation is injected by the doctor with a very small needle just below the wrinkles to be treated. The filling effect is variable and depends on the type of skin and the quality and quantity of hyaluronic acid used. The aesthetic result is not permanent, due to the progressive reabsorption of the substance which makes periodic repetition of the incira intervention necessary every 2-12 months depending on the case.
The use of hyaluronic acid is also applied in the correction of other aesthetic defects. It is used very often to fill small scars or to give fullness and firmness to thin lips. In the latter case, a preparation with a higher concentration of hyaluronic acid is used to obtain a greater volumizing effect.
The success of this product has contributed to its spread also in numerous cosmetics for private use. However, these are products with rather bland effects when compared to the subcutaneous injection of hyaluronic acid which is not by chance much more expensive (200-600 euros per session).
Recently some studies have shown that hyaluronic acid is also involved in the processes of proliferation and growth of hair and hair, opening new horizons in the cosmetic use of this important substance.
Osteoarthritis and hyaluronic acid
Hyaluronic acid is a fundamental component of synovial fluid. This liquid is placed inside the joints in order to protect the cartilage from wear and excessive loads. The synovial fluid, in addition to cushioning the movements, ensures the nourishment of the cartilage, accelerating the reparative processes.
Joint aging, like skin aging, is associated with a decrease in the production of synovial fluid.
We can compare the action of hyaluronic acid to that of the engine oil of a car. Over time, heat and friction decrease the viscosity of the oil, making it less effective in protecting mechanical parts. Hyaluronic acid behaves the same way inside the joints. An excessive decrease of this substance, linked to traumatic events or advancing age, in fact increases the friction between the articular surfaces.
Hyaluronic acid is particularly effective in the treatment and prevention of osteoarthritis, a degenerative pathology involving cartilage. In fact, intra-articular infiltrations of this substance can reduce pain while accelerating reparative processes. The therapy based on hyaluronic acid has proved to be effective above all in medium and modest lesions.
Also in this field, as in the aesthetic one, its action is not definitive and this makes it necessary to repeat the treatment every 6-12 months.
Additional applications
Hyaluronic acid is also used in ophthalmic, otological, ocular surgery and in the healing and tissue regeneration processes (it is for example the active ingredient of the drug Connettivina).