Biochemical Foundations of Human Vital Activity - Volkov, N. I., & Nesen, E. N. 2000

Biochemical Foundations of Human Vital Activity
Protein Biochemistry
Free Peptides and Their Role in the Organism

In recent years, particular interest has been drawn to the body's interstitial Peptides, which consist of a small number of Amino Acids (from 2 to 100) and perform independent, specific Functions. They are referred to as free or Natural peptides.

Free peptides include certain tissue Hormones (see Chapter 8), Neuropeptides, as well as such BIOLOGICALLY ACTIVE SUBSTANCES as Glutathione, anserine, carnosine, taurine, and numerous Antibiotics.

Neuropeptides, or the so-called opioid peptides, are found in the Brain as endorphins, enkephalins, dynorphin, and others. They influence the transmission of nerve impulses in the Central Nervous system and participate in the biochemical mechanisms underlying conditioned Reflexes that govern human behavior, emotions, and stress responses. A number of neuropeptides exhibit potent analgesic effects, nearly 30 times stronger than that of morphine. In effect, these are physiological dopings.

Glutathione is a tripeptide containing free sulfhydryl groups (SH) that participate in redox processes. It exerts a pronounced antioxidant effect by enhancing The breakdown of peroxides (H2O2) in Tissues, particularly in the brain and Blood. As a pharmacological agent, it is recommended for use as an antioxidant.

The dipeptides Carnosine and Anserine are found in skeletal Muscles, where they function as intracellular buffers.

Recently, the peptide taurine has been isolated from tissues. It is a sulfur-containing amine formed within tissues during the enzymatic Conversion of the amino acid Cysteine. Taurine regulates Cholesterol METABOLISM and exerts radioprotective effects, which is why it is widely used in clinical practice.



Last update: 06/08/2026

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