What's this
Collagen, in its hydrolyzed forms, is used in various fields of application, ranging from nutrition, medicine and cosmetics. We have seen that collagen as such is made up of long protein chains, which, for application purposes, are extracted and "cut" in order to obtain shorter peptides.
The further enzymatic degradation of the gelatin leads to the formation of a product which is called hydrolyzed collagen, which is characterized by a relatively low average molecular weight (3-6 kDa), by a high absorption and by a good bioavailability. It is generally obtained from bovine and pork collagen, although recently marine species represent an important source of hydrolyzed collagen.
Benefits compared to Collagen
In order to benefit the body it is essential that a compound taken orally is able to cross the intestinal barrier and, through the bloodstream, reach the compartments of the body where it is stored or used in the various metabolic processes.
In this regard, several studies have shown that hydrolyzed collagen is able to cross the intestinal barrier. Although it is believed that peptides are completely hydrolysed in the gastrointestinal tract in individual amino acids before absorption occurs, it has actually been shown that some of the peptides present in hydrolyzed collagen, particularly those containing hydroxyproline, are able to cross the intestinal barrier reaching the bloodstream and subsequently accumulating in the skin up to 96 hours later. In fact, it has been observed that following the oral intake of hydrolyzed collagen, the proline-hydroxyproline peptide is the most abundant peptide in the plasma.
Benefits
The use of drugs and supplements based on hydrolyzed collagen has long been known for its beneficial effects on joints, nails and hair, as well as showing antioxidant activity and antihypertensive properties.
By virtue of its ability to accumulate in the skin after oral intake, it has been hypothesized that hydrolyzed collagen could also play an important role in improving skin conditions, slowing the processes of premature aging and preserving it from photoinduced damage. These hypotheses have been demonstrated by observing that the orally administered hydrolyzed collagen is able to promote the expression, in the extracellular matrix of the skin, of type I collagen. This effect does not depend solely on the simple increase of amino acids available for protein synthesis, but it turned out to be a specific collagen effect. Clinical tests conducted in parallel have shown that protein hydrolysates other than collagen are not able to influence the synthesis of new collagen.
Therefore, supplementation with hydrolyzed collagen not only provides the "building blocks" for the synthesis of new collagen in the skin, but the peptides derived from collagen also play an active role in stimulating the biochemical processes that determine the formation of new structural protein fibers. In particular, the peptides containing proline and hydroxyproline, which as we have seen are characteristic of hydrolyzed collagen, act as biological messengers against fibroblasts, as they stimulate growth and migration in the skin, where they provide the synthesis of new collagen and reorganization of the extracellular matrix.
Furthermore, hydrolyzed collagen is able to inhibit the action of MMP2 (matrix type 2 metalloproteinases), consequently increasing the synthesis of type IV collagen, whose degradation is one of the causes that lead to the formation of wrinkles. In fact, it is hypothesized that the peptides that are absorbed in the gastrointestinal tract following the oral administration of hydrolyzed collagen, and that they accumulate in the skin, act by simulating the action of analogous peptides that form in the damaged skin, which inhibit further degradation of collagen by MMPs and at the same time stimulate the synthesis of new collagen by fibroblasts.
In the same way the long-term administration of hydrolyzed collagen is able to determine a significant inhibition of MMP1.
