Effect of tripeptide Lys-Glu-Asp on physiological activity of neuroimmunoendocrine system cells.

Tripeptide Lys-Glu-Asp stimulates proliferation and inhibits apoptosis in organotypic cultures of neuroimmunoendocrine system cells. Lys-Glu-Asp accelerates cell renewal processes (decrease of apoptosis marker p53 and increase of proliferation marker Ki-67) in the pineal gland; this effect is more pronounced in cultures derived from old animals than in young cultures. The tripeptide induces the expression of low-differentiated lymphocyte marker CD5 and macrophage marker CD68, but in "old" cultures this effect is less pronounced than in "young" ones. Thus, in tissue culture Lys-Glu-Asp primarily affects the nervous and endocrine tissues during aging and produces a less pronounced effect on the nervous tissue. Physiological activity of the tripeptide consists in modulation of associative learning of honey bee in the model of short-term and the long-term memory.