The value of blood plasma low-molecular-weight DNA for diagnostics of pathological processes of different genesis

Abstract

The low-molecular-weight DNA appears in blood plasma a few hours after exposure of rats to ionizing radiation, and its content correlates directly with the irradiation dose. Cloning has shown, that the lowmolecular-weight DNA is enriched with C + G pairs and features of its primary structure characterize its capacity to form rather stable nucleosomes. DNA isolated after irradiation of rats with principally different doses 8 and 100 Gy differed not only quantitatively, but also by the content of the dinucleotides CpG and CpT; this suggests that they originate from different regions of the genome. It has been shown for the first time that exposure of animals to low-frequency noise results in an increase of the content of blood plasma low-molecular-weight DNA. Strokes are characterized by the increase of this DNA during 3 days after the beginning of the acute period, and dynamics of its excretion differs in patients with ischemic and hemorrhagic forms of this disease. In the case of ischemia low-molecular-weight DNA appears in cerebrospinal fluid. In contrast to patients with non-obstructive chronic bronchitis, patients with the chronic obstructive pulmonary disease in the state of remission are characterized by decreased levels of blood plasma low-molecular-weight DNA. The clear dependence between formation and specific features of the low-molecular-weight DNA fraction in blood plasma suggests that it may serve as a universal quantitative marker of apoptosis, which differentiates basically different conditions of the body.