Extracellular DNA Affects NO Content in Human Endothelial Cells

• Published in: Bulletin of experimental biology and medicine Vol. 149; no. 2; pp. 196 - 200
• Main Authors: Efremova, L. V, Alekseeva, A. Yu, Konkova, M. S, Kostyuk, S. V, Ershova, E. S, Smirnova, T. D, Konorova, I. L, Veiko, N. N
• Format: Journal Article
• Language: English
• Published: Boston Boston : Springer US 01-08-2010; Springer US; Springer; Springer Nature B.V
• Subjects: Atherosclerosis; Atherosclerosis - metabolism; Biomedical and Life Sciences; Biomedicine; Cell Biology; Cells, Cultured; CG-DNA; DNA; DNA - genetics; DNA - metabolism; DNA synthesis; Endothelial Cells - metabolism; Endothelium; Estradiol - metabolism; Extracellular Space - metabolism; GC Rich Sequence - genetics; Genetic research; Genomics; Hormones, Sex; Hostages; Humans; Hydrogen Peroxide - metabolism; Hypertension; Hypertension - metabolism; In Vitro Techniques; Internal Medicine; Laboratory Medicine; Nitric oxide; Nitric Oxide - biosynthesis; Nitric Oxide - metabolism; Pathology; Spectrometry, Fluorescence; Umbilical Veins - cytology; CG-DNA; endothelium; nitric oxide
• ISSN: 0007-4888; 1573-8221
• DOI: 10.1007/s10517-010-0906-3

Fragments of extracellular DNA are permanently released into the blood flow due to cell apoptosis and possible de novo DNA synthesis. To find out whether extracellular DNA can affect the synthesis of nitric oxide (NO), one of key vascular tone regulators, we studied in vitro effects of three artificial DNA probes with different sequences and 10 samples of extracellular DNA (obtained from healthy people and patients with hypertension and atherosclerosis) on NO synthesis in endothelial cell culture (HUVEC). For detection of NO in live cells and culture medium, we used a NO-specific agent CuFL penetrating into the cells and forming a fluorescent product FL-NO upon interaction with NO. Human genome DNA fragments affected the content of NO in endothelial cells; this effect depended on both the base sequence and concentration of DNA fragments. Addition of artificial DNA and extracellular DNA from healthy people into the cell culture in a low concentration (5 ng/ml) increased the detected NO concentration by 4-fold at most. Cytosine-guanine (CG)-rich fragment of the transcribed sequence of ribosomal repeat was the most powerful NO-inductor. The effect of DNA fragments on NO synthesis was comparable with that of low doses of oxidizing agents, Н₂О₂ and 17β-estradiol. Extracellular DNA samples obtained from patients with hypertension and atherosclerosis decreased NO content in cells and medium by 1.3-28 times compared to the control; the effect correlated with the content of CG-rich sequences.