Endogenous neuropeptide cyclo-L-prolylglycine possesses mnemotropic and neuroprotective properties, which can result from its positive effect on the level of brain-derived neurotrophic factor and modulation of activity of insulin-like growth factor-1 and AMPA receptors. For detection of possible mitogenic action of cyclo-L-prolylglycine, we analyzed its effect on proliferative activity of HEK293 and SH-SY5Y cells assessed by expression of Ki-67 proliferation marker, cell cycle examination, and incorporation of modified nucleotide analog EdU into DNA. Cyclo-L-prolylglycine did not affect the level of Ki-67 in examined cell lines and distribution of the cells over G1 and G2 phases of the cell cycle, although it insignificantly reduced the percentage of S phase cells, which attested to the absence of intrinsic mitogenic activity of the peptide. At the same time, cyclo-L-prolylglycine reduced the number of the early apoptotic cells, which can be a mechanisms of its protective action.

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神经肽环-L-脯氨酰甘氨酸对细胞增殖活性的影响

内源性神经肽环-L-脯氨酰甘氨酸具有促记忆作用和神经保护特性，这可能是由于其对脑源性神经营养因子水平的积极影响以及对胰岛素样生长因子-1 和 AMPA 受体活性的调节。为了检测环-L-脯氨酰甘氨酸可能的促有丝分裂作用，我们分析了其对 HEK293 和 SH-SY5Y 细胞增殖活性的影响，通过 Ki-67 增殖标志物的表达、细胞周期检查和修饰的核苷酸类似物 EdU 掺入 DNA 来评估. 环-L-脯氨酰甘氨酸不影响检查细胞系中 Ki-67 的水平以及细胞在 G1 和 G2 期细胞周期的分布，尽管它微不足道地降低了 S 期细胞的百分比，这证明不存在肽的内在有丝分裂活性。