Nucleotides are the units that make up nucleic acids (DNA and RNA) or our genetic heritage. They play a key role in all cells; In particular, they have proven important in all situations of rapid growth, malnutrition, infection and trauma or damage, such as in peripheral nerve fibers in the presence of diabetes (diabetic neuropathy) or other situations. Several studies have documented an important nutraceutical role of nucleotides in the regeneration of tissues at high turnover rate such as peripheral nervous tissue. Nucleotides, long neglected, are now becoming a more common form of supplementation and gaining recognition both for their nutraceutical and immunostimulant and plastic-reconstructive properties. Research in these areas is ongoing.
What are nucleotides?
Nucleotides are the organic units that make up nucleic acids (DNA and RNA) or, more simply, our genetic code located inside the nucleus of each cell. A single nucleotide consists of three substances: a sugar, a nitrogenous base, and one or more phosphate groups. The most important are adenosine, guanosine, inosine, cytidine and uridine monophosphate. Nucleotides bind to each other through sugars to form long linear chains (polymers) that make up each nucleic acid (DNA or RNA).
The sequence of nucleotides DNA (deoxyribonucleic acid) affects the expression of our genes. The genes are more segments or less long of DNA (i.e. segments of nucleotides) which contain the information essential to the protein synthesis. Proteins consist of Amino acids and play a fundamental role in regulating the cellular mechanisms of an organism, including those of the nerve cell.
Uridine Monophosphate Cytidine Monophosphate
The nucleotide sequence of a given gene then specifies the amino acid sequence of the related protein.
Experts consider nucleotides to be “semi-essential” nutrients. What does it mean? It means that in normal conditions, for example of the nerves, endogenous production meets the needs, but during conditions of prolonged stress or damage to nerve fibers, exogenous administration is necessary.
Nucleotides play a key role in all cells and in the regeneration of nerve cells where they have long been studied as nutraceuticals thanks to the growing scientific knowledge on molecular biology, the physiology of the peripheral nervous system and the pathophysiology of healing.
The structure of peripheral nerves
The neuron or nerve cell is the basic unit of our nervous system. It is a complex cell, formed by a cell body with a central nucleus and various other structures important for the life of the cell. Lesions of the cell body can provoke deterioration of the entire neuron.
Neurons have long extensions called axons or nerve fibers (myelin-coated, see below) and dendrites, not coated with myelin. Axons carry nerve impulses away from the nerve cell while dendrites receive them from other neurons. Neurons can vary greatly from each other in terms of function, shape, cell body position, number and length of their axons. The end fibers of each axon have so-called synaptic buttons. These terminal nodes contain vesicles filled with neurotransmitters that carry impulses from one nerve cell to another.
Nerve conduction and myelin sheath
Nerve conduction along axons is accelerated thanks to the coating of nerve fibers with myelin pads. Myelin is an insulating lipid sheath (a bit like the plastic sleeve of electrical wires) that, produced by Schwann cells, surrounds most of the nerve fibers (axons) and allows the reliable a high speed of transmission of the nerve impulses within our body.
The myelin sheath, in fact, is not continuous. A well-defined intervals the sheath is interrupted and the axon is “naked” (called Ranvier nodes). In these nodes, the nerve impulse regenerates, restoring the intensity of the initial signal. In this way, the conduction of the impulse is not continuous, but “jumps” from one Ranvier node to another, with a faster mode of “jumping” type.
Peripheral nerve damage and regeneration
Myelin, therefore, guarantees a very high conduction speed, about 400 km per hour: faster than a Formula 1 racing car! An alteration or loss of the myelin sheath can slow down or even block the transmission of the nerve impulse, thus determining the onset of a whole series of symptoms and clinical signs.
In peripheral nerves, demyelination, thinning or sometimes complete loss of the myelin sheath, results from different conditions that can alter the Schwann cells that produce myelin or other constituents of the nerve or supporting cells.
The peripheral nervous system has the ability to regenerate thanks to Schwann cells. Studies have shown that after nerve damage, nucleotide integration promotes an adequate supply of the necessary substrates to accelerate nerve regeneration.
The role of nucleotides in peripheral nerve regeneration
Several studies have documented the biological role of nucleotides in the regeneration of high-throughput tissues such as peripheral nerve tissue. The regeneration and maintenance of the integrity of the myelin sheath are essential factors for the restoration of good conduction in case of peripheral neuropathy, for example in case of diabetic neuropathy.
Neoformation of the myelin sheath
3 Important aspects of the role of nucleotides
Nucleotides have been shown to be involved in the synthesis of phospholipids and glycolipids, the main components of the myelin sheath.
- Nucleotides are the precursors of nucleic acids (DNA and RNA) involved in the processes of protein synthesis, cellular metabolism, and nerve regeneration.
- Nucleotides activate powerful intracellular signals that stimulate Schwann cells to initiate myelin regeneration where it has been damaged.
- Some studies conducted with food supplements containing nucleotides at high doses in association with vitamin B1 and vitamin B12 have shown a further benefit in promoting the synthesis of phospholipids in the myelin sheath, in promoting an improvement in nerve impulse conduction, and in restoring muscle trophism in the damaged area.
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