NEUROENDOCRINOLOGY
LETTERS including Psychoneuroimmunology, Neuropsychopharmacology,
Reproductive Medicine, Chronobiology
and
Human Ethology
ISSN 0172–780X
We
have studied the effect of tetrapeptide Epitalon (Ala-Glu-Asp-Gly)
on the course of congenital pigmented degeneration of the
retina. The application of Epitalon in Campbell rats is found
to intensify the bioelectric and functional activity of the
retina due to the preservation of its morphological structure.
Epitalon therapy in patients with degenerative retinal lesions
results in a positive clinical effect in 90% of the cases.
The analysis of Epitalon effects suggests that the tetrapeptide
participates in the mechanisms of transcription common for
the epiphysis and retina.
Introduction
Treatment
for Retinitis Pigmentosa is a topical and socially relevant
problem. Degenerative processes of the retina are known to result
from disturbed metabolism of specific proteins in the pigmented
epithelium and other retinal layers [1, 2].
In this connection, it appears crucial to develop and study
pharmaceuticals, which can influence the structural and functional
specialisation of retinal cells and, thus, provide a pathogenetic
treatment for Retinitis Pigmentosa. Peptides of tissue-specific
effect seem to be the most promising physiologically active
substances. One of such compounds is tetrapeptide Epitalon (Ala-Glu-Asp-Gly)
obtained by targeted chemical synthesis [3]. This peptide has
been designed on the basis of the amino acid analysis of a complex
pharmaceutical isolated from the retina of animals (Retinalamin).
Retinalamin is included in the State Pharmacopoeia of the Russian
Federation [4]. To synthesise this peptide we have used four
amino acids detected in Retinalamin at the highest concentrations.
It must be emphasised that the compositions of synthetic peptides
designed according to the amino acid analyses of pharmaceuticals
from the epiphysis (Epithalamin) and retina (Retinalamin) are
identical. This identity can be explained by the common embryological
origin of the epiphysis and eye retina, i.e., from the same
progenitor cells of the anterior neural plate [5]. Moreover,
pinealocytes and photoreceptor cells demonstrate a considerable
similarity at the molecular level, in particular, in their transcription
patterns [6, 7, 8]. These facts suggest that Epitalon can restore
retinal function, as well as the function of the pineal gland.
Therefore, the purpose of our experimental and clinical investigations
is to study the effect of Epitalon on the course of congenital
pigmented retinal degeneration.
