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Photochemistry and Photobiology Jan 2022Recent studies have implicated subcellular microvesicle particles (MVP) in the ability of ultraviolet B radiation to exert both local and systemic effects. Indeed, UVB...
Recent studies have implicated subcellular microvesicle particles (MVP) in the ability of ultraviolet B radiation to exert both local and systemic effects. Indeed, UVB generates MVP (UVB-MVP) in human skin and systemically following phototherapy. The current studies were designed to test the hypothesis that the ability of UVB to generate MVP was dependent upon reactive oxygen species (ROS). To that end, we tested urine samples from subjects undergoing UVB phototherapy for the presence of isoprostanes as well as the oxidized guanosine derivative 8OHdG. We also conducted a clinical study in which volar forearms of subjects were treated with localized UVB and erythema/MVP measured. The same cohort was then treated with 7 days of vitamin C (2 g day ) and vitamin E (1000 IU day ), and UVB-induced MVPs tested on the contralateral forearm. Urine specimens from subjects undergoing phototherapy were found to have increased levels of isoprostanes and 8OHdG, with maximal levels noted 8-16 h post-treatment. Treatment with antioxidant vitamins resulted in diminished UVB-generated skin MVP to baseline levels. These studies suggest that whole-body UVB generates a systemic pro-oxidative response, and that antioxidants can attenuate localized skin UVB-MVPs.
Topics: 8-Hydroxy-2'-Deoxyguanosine; Humans; Isoprostanes; Reactive Oxygen Species; Skin; Ultraviolet Rays; Ultraviolet Therapy
PubMed: 34324712
DOI: 10.1111/php.13494 -
Scientific Reports Nov 2022Here we present a comprehensive mass cytometry analysis of peripheral innate lymphoid cell (ILC) subsets in relapsing/remitting MS (RRMS) patients prior to and after...
Here we present a comprehensive mass cytometry analysis of peripheral innate lymphoid cell (ILC) subsets in relapsing/remitting MS (RRMS) patients prior to and after onset of cladribine tablets (CladT). ILC analysis was conducted on CyTOF data from peripheral blood mononuclear cells (PBMC) of MS patients before, 2 and 6 months after onset of CladT, and non-MS controls. Dimensionality reduction was used for immunophenotyping ILC subsets. CladT reduced all ILC subsets, except for CD56bright NK cells and ILC2. Furthermore, CD38+ NK cell and CCR6+ ILC3 were excluded from CladT-induced immune cell reductions. Post-CladT replenishment by immature ILC was noted by increased CD5+ ILC1 proportions at 2 months, and boosted CD38-CD56bright NK cell numbers at 6 months. CladT induce immune cell depletion among ILC but exclude CD56bright NK cells and ILC2 subsets, as well as CD38+ NK cell and CCR6+ ILC3 immunophenotypes. Post-CladT ILC expansions indicate ILC reconstitution towards a more tolerant immune system phenotype.
Topics: Humans; Cladribine; Immunity, Innate; Multiple Sclerosis; Leukocytes, Mononuclear; Killer Cells, Natural
PubMed: 36437270
DOI: 10.1038/s41598-022-24617-4 -
Chemical Research in Toxicology Jun 2021The -alkylguanosine adduct -carboxymethyldeoxyguanosine (-CMdG) has been detected at elevated levels in blood and tissue samples from colorectal cancer patients and from...
The -alkylguanosine adduct -carboxymethyldeoxyguanosine (-CMdG) has been detected at elevated levels in blood and tissue samples from colorectal cancer patients and from healthy volunteers after consuming red meat. The diazo compound l-azaserine leads to the formation of -CMdG as well as the corresponding methyl adduct -methyldeoxyguanosine (-MedG) in cells and is therefore in wide use as a chemical probe in cellular studies concerning DNA damage and mutation. However, there remain knowledge gaps concerning the chemical basis of DNA adduct formation by l-azaserine. To characterize -CMdG formation by l-azaserine, we carried out a combination of chemical and enzymatic stability and reactivity studies supported by liquid chromatography tandem mass spectrometry for the simultaneous quantification of -CMdG and -MedG. We found that l-azaserine is stable under physiological and alkaline conditions as well as in active biological matrices but undergoes acid-catalyzed hydrolysis. We show, for the first time, that l-azaserine reacts directly with guanosine (dG) and oligonucleotides to form an -serine-CMdG (-Ser-CMdG) adduct. Moreover, by characterizing the reaction of dG with l-azaserine, we demonstrate that -Ser-CMdG forms as an intermediate that spontaneously decomposes to form -CMdG. Finally, we quantified levels of -CMdG and -MedG in a human cell line exposed to l-azaserine and found maximal adduct levels after 48 h. The findings of this work elucidate the chemical basis of how l-azaserine reacts with deoxyguanosine and support its use as a chemical probe for N-nitroso compound exposure in carcinogenesis research, particularly concerning the identification of pathways and factors that promote adduct formation.
Topics: Alkylation; Animals; Azaserine; Cells, Cultured; Deoxyguanosine; Humans; Hydrogen-Ion Concentration; Molecular Structure; Swine
PubMed: 34061515
DOI: 10.1021/acs.chemrestox.0c00471 -
BMC Public Health May 2023Regular sleep is very important for human health; however, the short-term and long-term effects of nightshift with sleep deprivation and disturbance on human metabolism,...
BACKGROUND
Regular sleep is very important for human health; however, the short-term and long-term effects of nightshift with sleep deprivation and disturbance on human metabolism, such as oxidative stress, have not been effectively evaluated based on a realistic cohort. We conducted the first long-term follow-up cohort study to evaluate the effect of nightshift work on DNA damage.
METHODS
We recruited 16 healthy volunteers (aged 33 ± 5 years) working night shifts at the Department of Laboratory Medicine at a local hospital. Their matched serum and urine samples were collected at four time points: before, during (twice), and after the nightshift period. The levels of 8-oxo-7,8-dihydroguanosine (8-oxoG) and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), two important nucleic-acid damage markers, were accurately determined based on a robust self-established LC‒MS/MS method. The Mann-Whitney U or Kruskal-Wallis test was used for comparisons, and Pearson's or Spearman's correlation analysis was used to calculate the correlation coefficients.
RESULTS
The levels of serum 8-oxodG, estimated glomerular filtration rate-corrected serum 8-oxodG, and the serum-to-urine 8-oxodG ratio significantly increased during the nightshift period. These levels were significantly higher than pre-nightshift work level even after 1 month of discontinuation, but no such significant change was found for 8-oxoG. Moreover, 8-oxoG and 8-oxodG levels were significantly positively associated with many routine biomarkers, such as total bilirubin and urea levels, and significantly negatively associated with serum lipids, such as total cholesterol levels.
CONCLUSION
The results of our cohort study suggested that working night shifts may increase oxidative DNA damage even after a month of discontinuing nightshift work. Further studies with large-scale cohorts, different nightshift modes, and longer follow-up times are needed to clarify the short- and long-term effects of night shifts on DNA damage and find effective solutions to combat the negative effects.
Topics: Humans; 8-Hydroxy-2'-Deoxyguanosine; Deoxyguanosine; Pilot Projects; Cohort Studies; Chromatography, Liquid; Follow-Up Studies; Tandem Mass Spectrometry; Oxidative Stress; Biomarkers
PubMed: 37189122
DOI: 10.1186/s12889-023-15742-4 -
Frontiers in Immunology 2022Adenosine synthase A (AdsA) is a key virulence factor of , a dangerous microbe that causes fatal diseases in humans. Together with staphylococcal nuclease, AdsA...
Adenosine synthase A (AdsA) is a key virulence factor of , a dangerous microbe that causes fatal diseases in humans. Together with staphylococcal nuclease, AdsA generates deoxyadenosine (dAdo) from neutrophil extracellular DNA traps thereby igniting caspase-3-dependent cell death in host immune cells that aim at penetrating infectious foci. Powered by a multi-technological approach, we here illustrate that the enzymatic activity of AdsA in abscess-mimicking microenvironments is not restricted to the biogenesis of dAdo but rather comprises excessive biosynthesis of deoxyguanosine (dGuo), a cytotoxic deoxyribonucleoside generated by to eradicate macrophages of human and animal origin. Based on a genome-wide CRISPR-Cas9 knock-out screen, we further demonstrate that dGuo-induced cytotoxicity in phagocytes involves targeting of the mammalian purine salvage pathway-apoptosis axis, a signaling cascade that is concomitantly stimulated by staphylococcal dAdo. Strikingly, synchronous targeting of this route by AdsA-derived dGuo and dAdo boosts macrophage cell death, indicating that multiplexes death-effector deoxyribonucleosides to maximize intra-host survival. Overall, these data provide unique insights into the cunning lifestyle of a deadly pathogen and may help to design therapeutic intervention strategies to combat multidrug-resistant staphylococci.
Topics: Animals; Deoxyadenosines; Mammals; Neutrophils; Staphylococcal Infections; Staphylococcus; Staphylococcus aureus
PubMed: 35355997
DOI: 10.3389/fimmu.2022.847171 -
Cells Mar 2022Acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) are characterized by genomic instability, which may arise from the global hypomethylation of the DNA....
Acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) are characterized by genomic instability, which may arise from the global hypomethylation of the DNA. The active DNA demethylation process may be linked with aberrant methylation and can be involved in leukemogenesis. The levels of 5-methylcytosine oxidation products were analyzed in minimally invasive material: the cellular DNA from peripheral blood cells and urine of patients with AML and MDS along with the control group, using isotope-dilution two-dimensional ultra-performance liquid chromatography with tandem mass spectrometry. The receiver operating characteristic curve analysis was used for the assessment of the ability to discriminate patients' groups from the control group, and AML from MDS. The most diagnostically useful for discriminating AML patients from the control group was the urinary excretion of 5-hydroxymethylcytosine (AUC = 0.918, sensitivity: 85%, and specificity: 97%), and 5-(hydroxymethyl)-2'-deoxyuridine (0.873, 74%, and 92%), while for MDS patients 5-(hydroxymethyl)-2'-deoxycytidine in DNA (0.905, 82%, and 98%) and urinary 5-hydroxymethylcytosine (0.746, 66%, and 92%). Multi-factor models of classification trees allowed the correct classification of patients with AML and MDS in 95.7% and 94.7% of cases. The highest prognostic value of the analyzed parameters in predicting the transformation of MDS into AML was observed for 5-carboxy-2'-deoxycytidine (0.823, 80%, and 97%) and 5-(hydroxymethyl)-2'-deoxyuridine (0.872, 100%, and 75%) in DNA. The presented research proves that the intermediates of the active DNA demethylation pathway determined in the completely non-invasive (urine) or minimally invasive (blood) material can be useful in supporting the diagnostic process of patients with MDS and AML. The possibility of an early identification of a group of MDS patients with an increased risk of transformation into AML is of particular importance.
Topics: DNA; DNA Demethylation; Deoxycytidine; Deoxyuridine; Humans; Leukemia, Myeloid, Acute; Myelodysplastic Syndromes; Prognosis
PubMed: 35269510
DOI: 10.3390/cells11050888 -
PloS One 2022Naked mole-rats are a long-lived rodent species (current lifespan >37 years) and an increasingly popular biomedical model. Naked mole-rats exhibit neuroplasticity across...
Naked mole-rats are a long-lived rodent species (current lifespan >37 years) and an increasingly popular biomedical model. Naked mole-rats exhibit neuroplasticity across their long lifespan. Previous studies have begun to investigate their neurogenic patterns. Here, we test the hypothesis that neuronal maturation is extended in this long-lived rodent. We characterize cell proliferation and neuronal maturation in established rodent neurogenic regions over 12 months following seven days of consecutive BrdU injection. Given that naked mole-rats are eusocial (high reproductive skew where only a few socially-dominant individuals reproduce), we also looked at proliferation in brain regions relevant to the social-decision making network. Finally, we measured co-expression of EdU (newly-born cells), DCX (immature neuron marker), and NeuN (mature neuron marker) to assess the timeline of neuronal maturation in adult naked mole-rats. This work reaffirms the subventricular zone as the main source of adult cell proliferation and suggests conservation of the rostral migratory stream in this species. Our profiling of socially-relevant brain regions suggests that future work which manipulates environmental context can unveil how newly-born cells integrate into circuitry and facilitate adult neuroplasticity. We also find naked mole-rat neuronal maturation sits at the intersection of rodents and long-lived, non-rodent species: while neurons can mature by 3 weeks (rodent-like), most neurons mature at 5 months and hippocampal neurogenic levels are low (like long-lived species). These data establish a timeline for future investigations of longevity- and socially-related manipulations of naked mole-rat adult neurogenesis.
Topics: Animals; Bromodeoxyuridine; Longevity; Mole Rats; Neurogenesis; Neurons
PubMed: 36107951
DOI: 10.1371/journal.pone.0273098 -
International Journal of Hygiene and... May 2023Oxidative stress is an important toxicity and genotoxicity mechanism of many chronic adverse health outcomes. This study developed a sensitive extraction method for...
Oxidative stress is an important toxicity and genotoxicity mechanism of many chronic adverse health outcomes. This study developed a sensitive extraction method for urine matrix (based on lyophilization, without the need for pre-cleaning by solid phase extraction), coupled to LC-MS/MS analysis of the biomarker 8-hydroxy-2'-deoxyguanosine (8-OHdG). The methodology was validated in urine samples from a cohort of Spanish pregnant women collected during the first, second and third trimester of pregnancy, and urine samples collected within 24 h after delivery (n = 85). A detection and quantification limit of 0.01 and 0.05 μg/L, respectively, were established. The median 8-OHdG concentration was 2.18 μg/L (range 0.33-7.79); and the corresponding creatinine-adjusted concentrations ranged from 1.04 to 13.12 with median of 4.48 μg 8-OHdG/g creatinine. The concentrations of non-adjusted 8-OHdG significantly decreased (p < 0.05) in the 3rd trimester and post-delivery urine samples when compared to the 1st trimester levels. 8-OHdG concentrations were further studied in placenta samples matching the same urine samples (n = 26), with a median value of 1.3 ng 8-OHdG/g of tissue. Placental 8-OHdG concentrations were correlated with urinary levels of non-adjusted 8-OHdG in the 3rd trimester. Considering the small cohort size, results must be interpreted with caution, however statistical analyses revealed elevated urinary non-adjusted 8-OHdG levels in the 1st trimester of mothers that delivered boys compared to those who delivered girls (p < 0.01). Increased urinary non-adjusted 8-OHdG concentrations at the time of delivery were significantly associated with clinical records (any type of clinical record during pregnancy; p < 0.05). The novel extraction and analytical method for the assessment of 8-OHdG is applicable for sensitive analysis of multiple analytes or biomarkers in urine matrix. This method could also be applied for other matrices such as blood or tissues. Our findings show that 8-OHdG in urine of pregnant women could predict oxidative stress in placenta and can be related to characteristics such as maternal obesity, mode of delivery and newborn sex.
Topics: Male; Infant, Newborn; Humans; Female; Pregnancy; 8-Hydroxy-2'-Deoxyguanosine; Deoxyguanosine; Pregnant Women; Chromatography, Liquid; Creatinine; Tandem Mass Spectrometry; Placenta; Biomarkers; Oxidative Stress; DNA Damage
PubMed: 37105016
DOI: 10.1016/j.ijheh.2023.114175 -
Biomolecules Nov 2021Bile duct cancer (BDC) has been identified as a highly aggressive cancer arising from epithelial cells of the bile duct, including intrahepatic, perihilar, and...
Bile duct cancer (BDC) has been identified as a highly aggressive cancer arising from epithelial cells of the bile duct, including intrahepatic, perihilar, and extrahepatic [...].
Topics: Aged; Bile Duct Neoplasms; Cholangiocarcinoma; Deoxycytidine; Humans; Middle Aged; Gemcitabine
PubMed: 34827625
DOI: 10.3390/biom11111626 -
International Journal of Molecular... Oct 2022The lack of effective treatments for mitochondrial disease has seen the development of new approaches, including those that stimulate mitochondrial biogenesis to boost...
The lack of effective treatments for mitochondrial disease has seen the development of new approaches, including those that stimulate mitochondrial biogenesis to boost ATP production. Here, we examined the effects of deoxyribonucleosides (dNs) on mitochondrial biogenesis and function in Short chain enoyl-CoA hydratase 1 (ECHS1) 'knockout' (KO) cells, which exhibit combined defects in both oxidative phosphorylation (OXPHOS) and mitochondrial fatty acid β-oxidation (FAO). DNs treatment increased mitochondrial DNA (mtDNA) copy number and the expression of mtDNA-encoded transcripts in both CONTROL (CON) and ECHS1 KO cells. DNs treatment also altered global nuclear gene expression, with key gene sets including 'respiratory electron transport' and 'formation of ATP by chemiosmotic coupling' increased in both CON and ECHS1 KO cells. Genes involved in OXPHOS complex I biogenesis were also upregulated in both CON and ECHS1 KO cells following dNs treatment, with a corresponding increase in the steady-state levels of holocomplex I in ECHS1 KO cells. Steady-state levels of OXPHOS complex V, and the CIII/CIV and CI/CIII/CIV supercomplexes, were also increased by dNs treatment in ECHS1 KO cells. Importantly, treatment with dNs increased both basal and maximal mitochondrial oxygen consumption in ECHS1 KO cells when metabolizing either glucose or the fatty acid palmitoyl-L-carnitine. These findings highlight the ability of dNs to improve overall mitochondrial respiratory function, via the stimulation mitochondrial biogenesis, in the face of combined defects in OXPHOS and FAO due to ECHS1 deficiency.
Topics: Organelle Biogenesis; Enoyl-CoA Hydratase; DNA, Mitochondrial; Fatty Acids; Glucose; Carnitine; Deoxyribonucleosides; Adenosine Triphosphate
PubMed: 36293464
DOI: 10.3390/ijms232012610