Extracellular DNA (ecDNA) activates immune cells and is involved in the pathogenesis of diseases associated with inflammation such as sepsis, rheumatoid arthritis or metabolic syndrome. DNA can be cleaved by deoxyribonucleases (DNases), some of which are secreted out of cells. The aim of this experiment was to describe plasma DNase activity in relation to extracellular DNA in adult rats, to analyse potential sex differences and to prove whether they are related to endogenous testosterone. Adult Lewis rats (n=28) of both sexes were included in the experiment. Male rats were gonadectomized or sham-operated and compared to intact female rats. Plasma ecDNA and DNase activity were measured using fluorometry and single radial enzyme diffusion assay, respectively. Concentrations of nuclear ecDNA and mitochondrial ecDNA were determined using real-time PCR. Females had 60% higher plasma DNase activity than males ( p=0.03). Gonadectomy did not affect plasma DNase in males. Neither the concentration of total ecDNA, nor nuclear or mitochondrial DNA in plasma differed between the groups. No significant correlations between DNase and ecDNA were found. From previous studies on mice, it was expected, that male rats will have higher DNase activity. In contrast, our study in rats showed the opposite sex difference. This sex difference seems not to be caused by endogenous testosterone. Interestingly, no sex differences were observed in plasma ecDNA suggesting a complex or missing association between plasma ecDNA and DNase. The observed sex difference in plasma DNase should be taken into account in animal models of ecDNA-associated diseases.

• MeSH
• deoxyribonukleasy krev   MeSH
• DNA krev   MeSH
• krysa rodu Rattus MeSH
• orchiektomie MeSH
• pohlavní dimorfismus * MeSH
• potkani inbrední LEW MeSH
• testosteron krev   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• deoxyribonukleasy MeSH
• DNA MeSH
• testosteron MeSH

Circulating extracellular DNA (ecDNA) is known to worsen the outcome of many diseases. ecDNA released from neutrophils during infection or inflammation is present in the form of neutrophil extracellular traps (NETs). It has been shown that higher ecDNA concentration occurs in a number of inflammatory diseases including inflammatory bowel disease (IBD). Enzymes such as peptidyl arginine deiminases (PADs) are crucial for NET formation. We sought to describe the dynamics of ecDNA concentrations and fragmentation, along with NETosis during a mouse model of chemically induced colitis. Plasma ecDNA concentration was highest on day seven of dextran sulfate sodium (DSS) intake and the increase was time-dependent. This increase correlated with the percentage of cells undergoing NETosis and other markers of disease activity. Relative proportion of nuclear ecDNA increased towards more severe colitis; however, absolute amount decreased. In colon explant medium, the highest concentration of ecDNA was on day three of DSS consumption. Early administration of PAD4 inhibitors did not alleviate disease activity, but lowered the ecDNA concentration. These results uncover the biological characteristics of ecDNA in IBD and support the role of ecDNA in intestinal inflammation. The therapeutic intervention aimed at NETs and/or nuclear ecDNA has yet to be fully investigated.

• Klíčová slova
• PAD4, cell-free DNA, deoxyribonuclease activity, neutrophil extracellular traps, ulcerative colitis,
• MeSH
• biologické markery metabolismus   MeSH
• deoxyribonukleasy metabolismus   MeSH
• DNA krev   metabolismus   MeSH
• endoskopie MeSH
• extracelulární pasti účinky léků   metabolismus   MeSH
• extracelulární prostor metabolismus   MeSH
• kolitida krev   chemicky indukované   patologie   MeSH
• mitochondriální DNA krev   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• ornithin analogy a deriváty   farmakologie   MeSH
• peptidylarginindeiminasa typu 4 metabolismus   MeSH
• síran dextranu MeSH
• streptonigrin farmakologie   MeSH
• střeva účinky léků   patologie   MeSH
• střevní sliznice účinky léků   patologie   MeSH
• stupeň závažnosti nemoci MeSH
• zánět krev   patologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• biologické markery MeSH
• deoxyribonukleasy MeSH
• DNA MeSH
• mitochondriální DNA MeSH
• N-alpha-benzoyl-N5-(2-chloro-1-iminoethyl)-L-ornithine amide MeSH Prohlížeč
• ornithin MeSH
• peptidylarginindeiminasa typu 4 MeSH
• peptidylarginine deiminase 4, mouse MeSH Prohlížeč
• síran dextranu MeSH
• streptonigrin MeSH