[Effect of genetically coded amino acids and their precursors carboxylic acids on the cellular proliferation in the organotypic culture of spleen in young and old rats].

Effect of carboxylic acids - structurally related to amino acids, on the proliferation activity of the cells in organotypic cultures of rat spleen was first studied. It was found that almost all aliphatic carboxylic acids have stimulating effects on proliferative activity of cells in young and old rats. In contrast only 3 from 14 active amino acids in young rats were able stimulate proliferation, but 11 amino acids inhibited it. In the old rats a number of the active amino acids was decreased until 4, an inhibiting effect was observed in 3 of them. Thus, the carboxylic acids are able to stimulate the regeneration processes in the immune tissue both in the young and old organisms. This fact can be a base for the research of new medical substances for the stimulation of the immunogenesis by the aging.

Effect of bioregulatory tripeptides on the culture of skin cells from young and old rats.

We studied the effects of synthesized tripeptides T-32 (Glu-Asp-Ala), T-33 (Glu-Asp-Arg), T-34 (Glu-Asp-Gly), T-36 (Glu-Asp-Pro), and T-38 (Lys-Glu-Asp) on organotypic skin cultures of young and old rats. In skin explants from young rats, all peptides except T-34 produced a stimulating effect on cell proliferation. In skin explants from old rats, tripeptide T-38 produced a marked stimulatory effect on proliferation. Immunocytochemical study of the proapoptotic p53 protein expression showed that cell proliferation increased due to less pronounced apoptosis. The capacity of the studied tripeptides to promote cell proliferation in the skin tissues of young and old animals provides the basis for further study of these substances as preparations boosting the regenerative processes in the skin, including those at age-associated pathology.