Effect of Peptide AEDG on Telomere Length and Mitotic Index of PHA-Stimulated Human Blood Lymphocytes

We studied the effect of peptide AEDG on telomere length and mitotic index of PHA-stimulated blood lymphocytes from young (18-22 years, N=5) and middle-aged (49-54 years, N=6) men. In the younger age group, no significant changes in the mitotic index were detected, while in the middle-aged group, a decrease in this parameter was found in one case. The relative length of telomeric regions of metaphase chromosomes was evaluated by in situ fluorescence hybridization with DNA probes specific to telomeres. After incubation with peptide AEDG, significant changes in the relative telomere length were found in 7 of 11 individuals (3 cases in the younger age group and 4 cases in the middle age group). Significant increase in telomere length after exposure to peptide AEDG was revealed in 5 cases, including two individuals of the younger age group (by 41 and 55%) and three individuals of the middle age group (by 156, 18, and 76%). In one individual of the younger age group and in one of the middle-age group, a significant decrease in telomere length (by 37 and 15%, respectively) was found. A tendency to normalization of telomere lengths was noted: this parameter increased in individuals with initially lower telomere length relative to the group mean value and decreased in individuals with initially longer telomeres compared to the mean length in the group.