DNase Research Articles

Melatonin Mediates Cardiac Tissue Damage under Septic Conditions Induced by Lipopolysaccharide.

Lipopolysaccharide (LPS) is known to induce oxidative stress and inflammation, leading to significant damage in cardiac tissues. This study investigates the protective effects of melatonin (MLT) against LPS-induced oxidative damage, inflammation, and apoptosis in rat heart tissue. Rats were divided into four groups (n = 6 per group): control, melatonin-treated, LPS-treated, and LPS + melatonin-treated. Oxidative stress markers, including thiobarbituric acid-reactive substances (TBARSs) and advanced oxidation protein products (AOPPs), were measured. Additionally, inflammatory markers, such as interleukin-6 (IL-6) levels, inducible nitric oxide synthase (iNOS) and nitric oxide (NO) content, and apoptotic markers, caspase-3, caspase-9, and acidic DNase activity, were evaluated. LPS treatment significantly increased TBARS, AOPP, and IL-6 levels, as well as the activity of caspase-3, acidic DNase and iNOS and NO content compared to the control group. Co-treatment with melatonin significantly reduced the levels of TBARS and AOPP levels, and caspase-3 and acidic DNase activities nearly matched those of the control group, while caspse-9 was still slightly increased. Interestingly, IL-6, iNOS and NO levels were significantly decreased but did not fully match the values in the control group. Melatonin mitigates LPS-induced oxidative stress, inflammation, and apoptosis in rat heart tissue by affecting all studied parameters, demonstrating its potential as a therapeutic agent for conditions characterized by oxidative stress and inflammation. Further research is warranted to explore the clinical applications of melatonin in cardiovascular diseases.

Direct whole-genome sequencing of HIV-1 for clinical drug-resistance analysis and public health surveillance

BackgroundHuman Immunodeficiency virus type 1 (HIV-1) remains a significant global health threat partly due to its ability to develop resistance to anti-retroviral therapies. HIV-1 genotype and drug resistance analysis of the polymerase (pol) sequence is a mainstay of its clinical and public health management. However, as new treatments and resistances evolve, analysis methods must change accordingly. In this study, we outline the development and implementation of a direct whole-genome sequencing approach (dWGS) using probe-capture target-enrichment for HIV-1 genotype and drug resistance analysis. MethodsWe implemented dWGS and performed parallel pol Sanger sequencing for clinical samples, followed by comparative genotype and drug-resistance analysis. These HIV-1 WGS sequences were also utilised for a novel partitioned phylogenetic analysis. ResultsOptimised nucleic acid extraction and DNAse I treatment significantly increased HIV-1 whole-genome coverage and depth, and improved recovery of high-quality genomes from low viral load clinical samples, enabling routine sequencing of viral loads as low as 1000 copies/mL. Overall, dWGS was robust, accurate and more sensitive for detecting low-frequency variants at drug-resistance sites compared to Sanger sequencing. Analysis of multiple sequence regions improved phylogenetic reconstruction for recombinant HIV-1 sequences compared to analysis of pol sequence alone. ConclusionsThese findings demonstrate dWGS enhances HIV-1 drug-resistance analysis by quantitative variant detection and improves reconstruction of HIV-1 phylogenies compared to traditional pol sequencing. This work supports that HIV-1 dWGS is a viable option to replace Sanger sequencing for clinical and public health applications.

Urinary Proteomics and Outcomes in Heart Failure With Preserved Ejection Fraction.

Although several studies have addressed plasma proteomics in heart failure with preserved ejection fraction, limited data are available on the prognostic value of urinary proteomics. The objective of our study was to identify urinary proteins/peptides associated with death and heart failure admission in patients with heart failure with preserved ejection fraction. The study population included participants enrolled in TOPCAT (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist Trial). The relationship between urine protein levels and the risk of death or heart failure admission was assessed using Cox regression, in both nonadjusted analyses and adjusting for urine creatinine levels, and the MAGGIC (Meta-Analysis Global Group in Chronic Heart Failure) score. A total of 426 (12.4%) TOPCAT participants had urinary protein data and were included. There were 40 urinary proteins/peptides significantly associated with death or heart failure admission in nonadjusted analyses, 21 of which were also significant adjusted analyses. Top proteins in the adjusted analysis included ANGPTL2 (angiopoietin-like protein 2) (hazard ratio [HR], 0.5731 [95% CI, 0.47-0.7]; P=3.13E-05), AMY2A (α amylase 2A) (HR, 0.5496 [95% CI, 0.44-0.69]; P=0.0001), and DNASE1 (deoxyribonuclease-1) (HR, 0.5704 [95% CI, 0.46-0.71]; P=0.0002). Higher urinary levels of proteins involved in fibrosis (collagen VI α-1, collagen XV α-1), metabolism (pancreatic α-amylase 2A/B, mannosidase α class 1A member 1), and inflammation (heat shock protein family D member 1, inducible T cell costimulatory ligand) were associated with a lower risk of death or heart failure admission. Our study identifies several novel associations between urinary proteins/peptides and outcomes in heart failure with preserved ejection fraction. Many of these associations are independent of clinical risk scores and may aid in risk stratification in this patient population.

Comprehensive Analysis Reveals Deoxyribonuclease 1 as a Potential Prognostic and Diagnostic Biomarker in Human Cancers.

Deoxyribonuclease 1 (DNASE1) is an important gene associated with several cancers, including liver, bladder, and gastric cancer. It has been linked to autoimmune illnesses, including systemic lupus erythematosus, which may lead to cancer formation. However, the role of DNASE1 in cancer has not beenstudied. We performed a pan-cancer analysis using bioinformatics tools, including Tumor Immune Estimation Resource (TIMER), Gene Expression Profiling Interactive Analysis (GEPIA), and University of Alabama at Birmingham Cancer Data Analysis Portal (UALCAN) databases, Kaplan-Meier plotter, and cBioPortal, to investigate the expression of DNASE1 across various cancers as well as its association with immune infiltration and genetic alterations. Public datasets were used to validate DNASE1 expression in kidney renal clear cell carcinoma (KIRC) and kidney papillary renal cell carcinoma (KIRP) samples. DNASE1 was found to be highly expressed in many cancers, such as bladder urothelial carcinoma (BLCA), breast invasive carcinoma (BRCA), head and neck squamous cell carcinoma (HNSC), and was lowly expressed in other cancers, including KIRC, KIRP, and thyroid carcinoma (THCA). Additionally, TIMER results showed an association of DNASE1 with immune cell infiltration in KIRC and KIRP. Survival analysis indicated that high DNASE1 expression was associated with poor prognosis in KIRC. We also discovered that altered DNASE1 expression was related to poor prognosis in The Cancer Genome Atlas (TCGA) tumors. DNASE1 could potentially be used as a prognostic and diagnostic biomarker for KIRC and as a diagnostic biomarker for KIRP.

Isolation and characterization of lactic acid bacteria with probiotic potential from traditional fermented special Kurdish cheese (Zhazhi) in Kurdistan Region, Iraq.

Zhazhi cheese is a unique farmhouse traditional fermented dairy of the Kurdistan Region in Iraq for its desired aroma and flavor. Undoubtedly, the lactic acid bacteria (LAB) are the critical factors in developing the aroma, flavor, and texture of Zhazhi cheese but it has not been studied or characterised. LAB has many important nutritional benefits, including increasing the nutritional value of food. Therefore, this research was performed to isolate and identify the potential probiotic LAB from traditional homemade Kurdish cheese. Then, the identified strains were tested to determine their probiotics traits, which include acid resistance, bile-salt tolerance, haemolytic, DNase, hydrophobic, autoaggregation, antimicrobial and antibiotic activities. The isolated five LAB strains comprised Lactobacillus casei, Lactobacillus rhamnosus, Enterococcus faecium, Pediococcus pentocaseus and Lactobacillus helvaticum were recognized as promising and the most potential probiotics for further applications. This is the first report on the direct selection of potentially probiotic LAB from Kurdish special cheese (Zhazhi).

Multidimensional evaluation of techno-functional properties of yoghurt bacteria

Microbial diversity in traditional foods is decreasing due to widespread industrial production, using a limited number of strains, and industrial products as starter cultures in homemade production. Yoghurt is a fermented product, and this decrease is most common. This study investigated the microbiological and physicochemical properties of 82 traditional and 37 industrial yoghurt samples. Four hundred thirty-nine lactic acid bacteria isolated were molecularly identified. Of the isolates, 223 were Lactobacillus bulgaricus, and 216 were Streptococcus thermophilus. Characteristics of the isolates such as acidification, arginine hydrolysis and gas production from glucose, H2O2 production, growth at different temperatures, pH and NaCl concentrations, exopolysaccharide production, proteolytic and lipolytic activity, l (+) lactic acid production, cholesterol assimilation, haemolytic activity, DNase activity, antibiotic resistance, and virulence gene were investigated. As a result, 4 L. bulgaricus and 6 S. thermophilus isolates were the best starter cultures for yoghurt production.

Breaking bad.

DNASE1 (D1) and DNASE1L3 (D1L3) synergistically reduce the severity of systemic infections caused by Staphylococcus aureus. In this issue of JEM, Lacey et al. (2023. J. Exp. Med.https://doi.org/10.1084/jem.20221086) develop D1-/-, D1L3-/-, and D1-/-D1L3-/- mice to show that exogenous addition of the DNase formulation Dornase alfa can facilitate removal of biofilms.

Fragmentation landscape of cell-free DNA revealed by deconvolutional analysis of end motifs

Cell-free DNA (cfDNA) fragmentation is nonrandom, at least partially mediated by various DNA nucleases, forming characteristic cfDNA end motifs. However, there is a paucity of tools for deciphering the relative contributions of cfDNA cleavage patterns related to underlying fragmentation factors. In this study, through non-negative matrix factorization algorithm, we used 256 5' 4-mer end motifs to identify distinct types of cfDNA cleavage patterns, referred to as "founder" end-motif profiles (F-profiles). F-profiles were associated with different DNA nucleases based on whether such patterns were disrupted in nuclease-knockout mouse models. Contributions of individual F-profiles in a cfDNA sample could be determined by deconvolutional analysis. We analyzed 93 murine cfDNA samples of different nuclease-deficient mice and identified six types of F-profiles. F-profiles I, II, and III were linked to deoxyribonuclease 1 like 3 (DNASE1L3), deoxyribonuclease 1 (DNASE1), and DNA fragmentation factor subunit beta (DFFB), respectively. We revealed that 42.9% of plasma cfDNA molecules were attributed to DNASE1L3-mediated fragmentation, whereas 43.4% of urinary cfDNA molecules involved DNASE1-mediated fragmentation. We further demonstrated that the relative contributions of F-profiles were useful to inform pathological states, such as autoimmune disorders and cancer. Among the six F-profiles, the use of F-profile I could inform the human patients with systemic lupus erythematosus. F-profile VI could be used to detect individuals with hepatocellular carcinoma, with an area under the receiver operating characteristic curve of 0.97. F-profile VI was more prominent in patients with nasopharyngeal carcinoma undergoing chemoradiotherapy. We proposed that this profile might be related to oxidative stress.

Efficient Detection of Biomarker of Radiation-Resistant Nasopharyngeal Carcinoma by Anchor Nucleic Acid Structure and DNase I Amplification

Radiotherapy is a simple and effective method for the treatment of rhinitis cancer, but some patients are resistant to radiotherapy and affect the curative effect. Previous studies have confirmed that miR-205 can be used as a biomarker for the feasibility of radiotherapy in nasopharyngeal carcinoma (NPC). In this study, a biosensor for the detection of miR-205 was constructed by using graphene oxide (GO) and fluorescent DNA probes, and using DNase I to generate fluorescent signals for cyclic amplification. The results showed that the lowest detection limit of this sensor for detecting miR-205 was 475 pM, which was 4.86 times lower or 4.86 times better than that of conventional methods without amplification, and showed better detection specificity. It is expected to provide a convenient and effective tool for studying the radio resistance mechanism of NPC and for personalized therapy for NPC patients.

Neutrophil extracellular traps (NETs) in aortic stenosis: Comparison of methods for assessment of NETs formation

Abstract Introduction We previously showed increased neutrophil extracellular traps (NETs) formation (NETosis) in patients with severe aortic stenosis (AS). Our aim was to comprehensively assess NETosis in AS using a relatively simple and appropriate technique. We investigated circulating NETosis markers by ELISA and assessed the potential of blood neutrophils to release NETs by flow cytometry. Materials and Methods We enrolled 13 patients aged 66 [Q1–Q3, 60–70] years with severe isolated AS without diabetes, chronic kidney disease, and atrial fibrillation. Nine apparently healthy volunteers of similar sex and age served as controls. Serum concentrations of citrullinated histone H3 (citH3), circulating nucleosomes, myeloperoxidase (MPO), and deoxyribonuclease-1 (DNASE1) were measured using ELISAs. Peripheral blood NET-releasing neutrophils were detected by flow cytometry as MPO/citH3-positive cells. Results AS patients compared to controls presented 174% higher concentrations of citH3 (p<0.001), 456% higher nucleosomes (p<0.001), 136% higher MPO (p=0.021) and 19% higher DNASE1 levels (p=0.039), together with 101% elevated percentage of NET-releasing neutrophils assessed by flow cytometry (p=0.003). In AS patients, the proportion of blood NET-releasing neutrophils positively correlated with citH3 (r=0.86, p<0.001) and nucleosome (r=0.58, p=0.041) concentrations but not with MPO or DNASE1. Moreover, we observed a strong association between AS severity, measured as aortic valve area (AVA), and serum citH3 concentrations (r=−0.75, p=0.003), but not the number of NET-releasing neutrophils. Conclusions Our study showed increased blood neutrophil potential to release NETs together with increased levels of serum markers of NETos is in severe AS patients. However, we recommend ELISA to assess NETosis in vivo as simpler technique giving more unequivocal results compared to flow cytometry.

Geometry guided crystallization of anisotropic DNA origami shapes.

Three-dimensional assembly based on DNA origami structures is an ideal method to precisely fabricate nano-scale materials. Additionally, applying an anisotropic assembly unit facilitates constructing complex materials with extraordinary structure. However, it still remains challenging to crystallize anisotropic DNA nano-structures using simple design, because the assembly of low-symmetry monomers often requires harsh auxiliary conditions and more complicated crystallization processes. In this work, we managed to crystallize the anisotropic elongated octahedral DNA origami frames by non-specific connections, and acquired two kinds of highly ordered superlattices purely by conducting multiple annealing processes and increasing the rigidity of the connection parts. In the case where the connection parts were composed of soft DNA sticky ends, we obtained the theoretically inaccessible simple cubic superlattices by this anisotropic DNA origami shape. Through characterization by small-angle X-ray scattering and scanning electron microscopy, we found that the DNA monomers are arbitrarily arranged due to the stress buffering of the soft DNA SEs, while in the stiffer case, simple tetragonal superlattices with translational arrangement of most anisotropic DNA origami shapes were synthesized as expected. This work deepened the understanding of geometry-guided crystallization of DNA origami shapes and provided a new path for constructing three-dimensional functional devices with simple design.

The Role of Nucleases Cleaving TLR3, TLR7/8 and TLR9 Ligands, Dicer RNase and miRNA/piRNA Proteins in Functional Adaptation to the Immune Escape and Xenophagy of Prostate Cancer Tissue.

The prototypic sensors for the induction of innate and adaptive immune responses are the Toll-like receptors (TLRs). Unusually high expression of TLRs in prostate carcinoma (PC), associated with less differentiated, more aggressive and more propagating forms of PC, changed the previous paradigm about the role of TLRs strictly in immune defense system. Our data reveal an entirely novel role of nucleic acids-sensing Toll-like receptors (NA-TLRs) in functional adaptation of malignant cells for supply and digestion of surrounding metabolic substrates from dead cells as specific mechanism of cancer cells survival, by corresponding ligands accelerated degradation and purine/pyrimidine salvage pathway. The spectrophotometric measurement protocols used for the determination of the activity of RNases and DNase II have been optimized in our laboratory as well as the enzyme-linked immunosorbent method for the determination of NF-κB p65 in prostate tissue samples. The protocols used to determine Dicer RNase, AGO2, TARBP2 and PIWIL4 were based on enzyme-linked immunosorbent assay. The amount of pre-existing acid-soluble oligonucleotides was measured and expressed as coefficient of absorbance. The activities of acid DNase II and RNase T2, and the activities of nucleases cleaving TLR3, TLR7/8 and TLR9 ligands (Poly I:C, poly U and unmethylated CpG), increased several times in PC, compared to the corresponding tumor adjacent and control tissue, exerting very high sensitivity and specificity of above 90%. Consequently higher levels of hypoxanthine and NF-κB p65 were reported in PC, whereas the opposite results were observed for miRNA biogenesis enzyme (Dicer RNase), miRNA processing protein (TARB2), miRNA-induced silencing complex protein (Argonaute-AGO) and PIWI-interacting RNAs silence transposon. Considering the crucial role of purine and pyrimidine nucleotides as energy carriers, subunits of nucleic acids and nucleotide cofactors, future explorations will be aimed to design novel anti-cancer immune strategies based on a specific acid endolysosomal nuclease inhibition.

The activity of lysosomal enzymes in organs of the White Sea mussel Mytilus edulis L. under crude oil impact in different salinity conditions

The effect of the toxicant on the activity of lysosomal hydrolases in organs of the White Sea mussels Mytilus edulis (Linnaeus 1758) was studied in aquatic experiments simulating a crude oil spill in the tidal zone. The mollusks were exposed for 1, 5 and 10 days to three pollutant concentrations (0.05; 0.25, and 2.50 ml/l). The impact of oil pollution was studied in combination with salinity normal for White Sea surface water (25 ‰) and low (15 ‰), which corresponds to reality during oil spills on the coast and in estuaries. We determined the activity of six lysosomal enzymes (acid phosphatase, RNase, DNase, β-glucosidase, β-galactosidase, and β-glucuronidase) in the gills and hepatopancreas. Both factors (sea water desalination and oil impact) had a significant effect on the activity of acid hydrolases. The most pronounced lysosomal reaction to oil appeared in the gills under normal salinity at 0.25 ml/l concentration and exposure for 10 days, as evidenced by a several-fold increase in the activity of acid phosphatase, DNase, β-galactosidase, and β-glucuronidase compared to the control. In the hepatopancreas, the same dependence in enzyme activity was noted, but to a lesser extent. Seawater desalination to 15 ‰ in the control caused a slight increase in the activity of DNase, β-galactosidase, and β-glucuronidase in the gills, while the effect for the hepatopancreas was insignificant. The combined effect of desalination and oil pollution somewhat reduced the protective functions of the lysosomal apparatus in mussels organs, which was especially noticeable at high oil concentrations and prolonged exposure of mollusks to experimental conditions. Thus, the results of the study demonstrate active participation of the lysosomal apparatus of the gills and hepatopancreas of mollusks in the adaptive responses to the combined effects of oil pollution and low water salinity. Compensatory changes in the activity of the enzyme complex of lysosomes are aimed at the utilization, transformation and excretion of oil components from the body, elimination of the structures and macromolecules damaged by the toxicant, as well as maintaining the vital activity of the organism under adverse conditions.

Tissue plasminogen activator with prolonged dwell time effectively evacuates pleural effusions

ObjectivesFibrinolytic therapy can be effective for management of complex pleural effusions. Tissue plasminogen activator (tPA, 10 mg) and deoxyribonuclease (DNAse) every 12 h with a dwell time of one hour is a common strategy based on published data. We used a simpler protocol of tPA (4 mg) without DNAse but with a longer dwell time of 12 h, repeated daily. We reviewed our results.MethodsCharts were reviewed and demographics, clinical data and treatment information were abstracted. Outcomes were assessed based on radiographic findings and need for surgery.ResultsTwo hundred and fifteen effusions in 207 patients (8 bilateral) were identified. 85% were either infectious or malignant. Two hundred and forty nine chest tubes were used: 84% were 10 Fr or 12 Fr and 7% were PleurX®. Five hundred and thirty one doses of tPA were given. The median number of doses per effusion was 2 (range 1–10), and 84% of effusions were treated with three or fewer doses. There were no significant bleeding complications. Median time to chest tube removal was 6 days (range 1 to 98, IQR 4 to 10). Drainage was considered complete for 78% of effusions, while 6% required decortication.ConclusionsLow dose tPA daily with a 12 h dwell time may be as effective as the standard regimen of tPA and DNAse twice daily with one hour dwell. For most patients only three doses were required, and small pigtail catheters were sufficient. This regimen uses less medication and is logistically much easier than the current standard.

Monogenic systemic lupus erythematosus associated with DNASE1 gene mutation: a case report and literature review

A retrospective analysis of the clinical features and genetic test results of a child with monogenic systemic lupus erythematosus (SLE) associated with a mutation in the deoxyribonuclease 1 (DNASE1) gene who presented to the First People's Hospital of Jingzhou City, Hubei Province in July 2021. The child was a female, 1 year and 5 months old, with recurrent fever, facial erythema, lupus-like rash on the trunk, positive for anti-nuclear and anti-Sm antibodies, and whole exon sequencing results suggested that the SLE susceptibility gene DNASE1, chr16:3705860, had a G>A mutation at locus c.158, and generation sequencing family verification presumed that the heterozygous mutation originated from the mother. This mutation has not been reported in China and expands the spectrum of pathogenic variants in SLE in China

DNASE-MEDIATED DISSOLUTION OF NEUTROPHIL EXTRACELLULAR TRAPS ACCELERATES IN VITRO THROMBIN GENERATION KINETICS IN TRAUMA PATIENTS.

Introduction: Neutrophil extracellular traps (NETs) trigger thrombin generation. We aimed to characterize the effects of deoxyribonuclease (DNAse) on NET components (cell-free DNA [cfDNA] and histones) and thrombin generation after trauma. Methods: Citrated plasma samples were collected from trauma patients and healthy volunteers. Thrombin generation (calibrated automated thrombogram) was measured as lag time (LT, in minutes), peak height (in nM), and time to peak thrombin generation (in minutes). Citrullinated histone 3 (CitH3) and 4 (CitH4) were measured by enzyme-linked immunosorbent assay; cfDNA by PicoGreen (all in nanograms per milliliter). Samples analyzed +/- DNAse (1,000 U/mL). Results expressed as median and quartiles [Q1, Q3], Wilcoxon testing, P < 0.05 significant. Results: We enrolled 46 patients (age, 48 [31, 67] years; 67% male) and 21 volunteers (age, 45 [28, 53] years; 43% male). Deoxyribonuclease treatment of trauma plasma led to shorter LT (3.11 [2.67, 3.52] min; 2.93 [2.67, 3.19] min), shorter time to peak thrombin generation (6.00 [5.30, 6.67] min; 5.48 [5.00, 6.00] min), greater peak height (273.7 [230.7, 300.5] nM; 288.7 [257.6, 319.2] nM), decreased cfDNA (576.9 [503.3, 803.1] ng/mL; 456.0 [393.5, 626.7] ng/mL), decreased CitH3 (4.54 [2.23, 10.01] ng/mL; 3.59 [1.93, 7.98] ng/mL), and increased H4 (1.30 [0.64, 6.36] ng/mL; 1.75 [0.83, 9.67] ng/mL), all P < 0.001. The effect of DNAse was greater on trauma patients as compared with volunteers for LT (ΔLT, -0.21 vs. -0.02 min, P = 0.007), cfDNA (ΔcfDNA -133.4 vs. -84.9 ng/mL, P < 0.001), and CitH3 (ΔCitH3, -0.65 vs. -0.11 ng/mL, P = 0.004). Conclusion: Deoxyribonuclease treatment accelerates thrombin generation kinetics in trauma patient samples as compared with healthy volunteers. These findings suggest that NETs may contribute to the hypercoagulable state observed in trauma patients.

Fragmentomics of urinary cell-free DNA in nuclease knockout mouse models.

Urinary cell-free DNA (ucfDNA) is a potential biomarker for bladder cancer detection. However, the biological characteristics of ucfDNA are not well understood. We explored the roles of deoxyribonuclease 1 (DNASE1) and deoxyribonuclease 1-like 3 (DNASE1L3) in the fragmentation of ucfDNA using mouse models. The deletion of Dnase1 in mice (Dnase1-/-) caused aberrations in ucfDNA fragmentation, including a 24-fold increase in DNA concentration, and a 3-fold enrichment of long DNA molecules, with a relative decrease of fragments with thymine ends and reduction of jaggedness (i.e., the presence of single-stranded protruding ends). In contrast, such changes were not observed in mice with Dnase1l3 deletion (Dnase1l3-/-). These results suggested that DNASE1 was an important nuclease contributing to the ucfDNA fragmentation. Western blot analysis revealed that the concentration of DNASE1 protein was higher in urine than DNASE1L3. The native-polyacrylamide gel electrophoresis zymogram showed that DNASE1 activity in urine was higher than that in plasma. Furthermore, the proportion of ucfDNA fragment ends within DNase I hypersensitive sites (DHSs) was significantly increased in Dnase1-deficient mice. In humans, patients with bladder cancer had lower proportions of ucfDNA fragment ends within the DHSs when compared with participants without bladder cancer. The area under the curve (AUC) for differentiating patients with and without bladder cancer was 0.83, suggesting the analysis of ucfDNA fragmentation in the DHSs may have potential for bladder cancer detection. This work revealed the intrinsic links between the nucleases in urine and ucfDNA fragmentomics.

Discovery of deoxyribonuclease II-like proteins in bacteria

Deoxyribonuclease II (DNase II) is one of the earliest enzymes discovered in the history of biochemistry. Its role in apoptosis and development has been documented with great detail in eukaryotes. Prior in silico analyses showed its complete absence in bacterial genomes, with the exception of single bacterial genus: Burkholderia. It is therefore considered to be a eukaryotic enzyme. Here we show that the presence of DNase II is not limited to Burkholderia, as we find over one hundred DNase II-like sequences spanning 90 bacteria species belonging to 54 different genera and seven phyla. The majority of the significant hits (85%) come from Bacteroidetes and Proteobacteria phyla. Sequence analyses reveal that bacterial DNase II-like proteins possess a signature catalytic motif of eukaryotic DNase II. In phylogenetic analyses, we find that bacterial DNase II-like proteins are divided into two distinct clades. Our structural analyses reveal high levels of similarity between experimentally determined crystal structures of recombinant Burkholderia thailandensis DNase II and candidate bacterial DNase II-like proteins. We also biochemically show that Chromobacterium violaceum cell lysate possesses acidic DNase II-like activities. Collectively, our results indicate that DNase II has deeper evolutionary roots than previously thought. We argue that either some prokaryotic lineages have undergone losses of DNase II genes, resulting in rare conservation, or some lineages have acquired DNase II genes from eukaryotes through lateral gene transfer. We also discuss the possible involvement of DNase II as a part of an anti-phage defense system in bacteria.

Comparison of toxic effects of lead and copper and protective power of glutathione on oxidative stress parameters

IntroductionLead as an industrial pollutant can be detected at all stages of the working and living environment. Lead, based on its properties, solubility and mobility, accumulates in the soil, so that the average concentrations of oil in the soil are between 15 and 25 mg/kg (Radojević at all., 1999). Due to increased human activity, the amount of copper in the air, soil and water has increased. Glutathione (GSH) is an essential cofactor of many enzymes, such as: formaldehyde dehydrogenase, glyoxalase, prostaglandin endoperoxide isomerase, dehydrochlorinase and others. GSH is a biological redox in the metabolism of erythrocytes, it also plays a role in the transport of amino acids. Reactive forms of oxygen cause oxidative biomolecules (lipids, proteins, DNA) (Freidovich, 1999; Massaad i Klann, 2010).ObjectivesThe aim of this research was to examine the protective role of supplements GSH in conditions of chronic intoxication with sublethal doses of lead acetate and copper II sulfate.MethodsThe preparation of biomaterials for testing and making homogenates of brain tissue of albino rats of Wistar strain was performed and the activity of acid and alkaline DNase was measured spectrophotometrically (Kocić i sar., 1998).ResultsLead otherwise “as soft Lewis acid” has a pronounced affinity for interaction with “soft bases” such as S-atoms of the thiol group in antioxidants, natural biomolecules and supplements in this case in glutathione.ConclusionsIt can be said that GSH is a desirable supplement and antioxidant in the detoxification of reactive oxygen species in rats exposed to lead poisoning.DisclosureNo significant relationships.

Protective role of glutathione in oxidative stress caused by cadmium and copper

IntroductionCadmium is defined as one of the leading toxic industrial pollutants (Valko i sar., 2005). Although some products containing cadmium can be recycled, much of the pollution with this metal is the result of inadequate disposal and uncontrolled incineration of cadmium-containing waste (Jarup, 2003). Copper particles are released into the atmosphere from copper smelters and ore processing facilities, as well as from anthropogenic sources (use of pesticides, herbicides and fungicides). Oxidative stress occurs due to increased production of reactive oxygen species (Parkinson’s and Alzheimer’s disease) or reduced ability of cells to neutralize it through their internal antioxidants (eg mutation of the superoxide dismutase gene in amyotrophic lateral sclerosis).ObjectivesThe aim of this research was to examine the protective role of supplement, GSH, S-donor ligand, and in conditions of acute and chronic intoxication with sublethal doses of cadmium-II-chloride and copper II sulfate.MethodsAfter medial laparotomy albino rates Wistar soy, a 10% homogenate of brain tissue was made in an appropriate medium and an analysis of acid and alkaline DNase activity was performed (Kocić i sar., 2004; Kocić i sar., 1998).ResultsThis experiment demonstrated the beneficial role of GSH supplement that exhibit antioxidant character in preventing and reducing the adverse effects of acute and chronic cadmium and copper intoxication.ConclusionsAntioxidants prevent the formation of oxidative stress in the cell by reducing and stopping DNA damage and degradation, and thus represent potential scavengers of free radicals.DisclosureNo significant relationships.