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.