Oxidative DNA damage has been associated with cognitive decline. The Ogg1 and Mutyh DNA glycosylases cooperate to prevent mutations caused by 8-oxoG, a major premutagenic oxidative DNA base lesion. Here, we have examined behavior and cognitive function in mice deficient of these glycosylases. We found that Ogg1-/-Mutyh-/- mice were more active and less anxious and that their learning ability was impaired. In contrast, Mutyh-/- mice showed moderately improved memory compared to WT. There was no change in genomic 8-oxoG levels, suggesting that Ogg1 and Mutyh play minor roles in global repair in adult brain. Notably, transcriptome analysis of hippocampus revealed that differentially expressed genes in the mutant mice belong to pathways known to be involved in anxiety and cognitive function. Thus, beyond their involvement in DNA repair, Ogg1 and Mutyh modulate cognitive function and behavior, and related hippocampal gene expression, suggesting a novel role for 8-oxoG in regulating adaptive behavior. Overall design: The mRNA profiles from hippocampus of WT, Ogg1-/-, Mutyh-/- and Ogg1-/- Mutyh-/- C57BL/6 mice at 6month of age were generated by RNA sequencing using Illumina Hiseq 2000
Synergistic Actions of Ogg1 and Mutyh DNA Glycosylases Modulate Anxiety-like Behavior in Mice.
Age, Specimen part, Cell line, Subject
View SamplesPurpose: The oxidation resistance gene 1 (OXR1) is crucial for protecting against oxidative stress, limiting neurodegeneration and maintaining normal lifespan in eukaryotes. However, the molecular function of OXR1 is still unknown. Previously we showed that human OXR1 regulates expression of antioxidant genes GPX2 and HO-1 via the p21 signaling pathway. To examine the role of hOXR1 in global transcription regulation during cellular stress, we employed RNA sequencing to investigate the transcription profile in hOXR1 depleted HeLa cells. Methods: Control siRNA (siCon) and human OXR1 siRNA (siOXR1) transfected HeLa cells were either harvested directly (siCon_NT, siOXR1_NT) or exposed to 0.5 mM H2O2 for 1 h and then harvested immediately without recovery (siCon_R0h, siOXR1_R0h). Total RNA pooled from duplicate samples was used for RNA sequencing on an Illumina HiSeq2000 platform. The sequence reads that passed quality filters were analyzed at gene level. The Blast2GO program was used to generate gene ontology (GO) annotation of differentially expressed genes (DEGs).The WEGO software was used to further perform GO functional classification and to predict pathways affected. qRT–PCR validation was performed using SYBR Green assays. Results: In total, in non-treated and hydrogen peroxide exposed cells, hOXR1 depletion results in the down-regulation of 554 genes and the up-regulation of 253 genes. These differentially expressed genes include transcription factors (i.e. HIF1A, SP6, E2F8 and TCF3) and numerous genes of the p53 signaling pathway involved in cell-cycle arrest (i.e. cyclin D, CDK6 and p21) and apoptosis (i.e. CytC and CASP9). Western blot analysis reveals that hOXR1 suppresses CASP9 protein expression and reduces post-translational cleavage into its active form. After exposure to hydrogen peroxide (1 h), 56 early response genes were up-regulated in hOXR1 depleted cells, in which 38 of these genes were not induced in control cells. In addition, a subset of the commonly up-regulated early response genes showed a stronger induction in hOXR1 depleted cells (i.e. FOS, JUN and DUSP1). Out of a total of 52 differentially expressed transcription factors in hOXR1 depleted cells under normal physiology and oxidative stress condition, 14 genes (including HIF1A, STAT5A, E2F8 and TCF3) are differentially regulated under H2O2 treatment in hOXR1 silenced cells as compared to control cells. Finally, we demonstrate that hOXR1 depleted cells undergo cell cycle arrest in G2/M phase during oxidative stress. Conclusions: Human OXR1 is important for regulation of the early stress response to oxidative stress in HeLa cells. HOXR1 modulates the p53 signaling pathway via regulation of genes involved in cell cycle arrest, apoptosis and anti-oxidation. Further, hOXR1 regulates numerous transcription factors of importance for cellular stress responses. In summary, hOXR1 may act as a sensor of cellular oxidative stress to regulate the transcriptional networks required to detoxify reactive oxygen species (ROS) and modulate cell cycle arrest and cell death (apoptosis). Overall design: The mRNA profiles of hOXR1 depleted and control Hela cells with or without H2O2 treatment 1 h were generated by RNA sequencing using Illumina Hiseq 2000.
Transcriptome analysis of human OXR1 depleted cells reveals its role in regulating the p53 signaling pathway.
No sample metadata fields
View SamplesThe aim of the present study was to examine potential differences in the regulation of myocardial ECM constituents, in mice that develop hypertrophy only (ABnonHF) and in mice that develop overt heart failure (ABHF) as response to pressure overload.
Differential regulation of extracellular matrix constituents in myocardial remodeling with and without heart failure following pressure overload.
Specimen part, Treatment
View SamplesMyocardial infarction (MI) triggers a reparative response involving fibroblast proliferation and differentiation driving extracellular matrix modulation necessary to form a stabilizing scar. Recently, it was shown that a genetic variant of the base excision repair enzyme endonuclease VIII-like 3 (NEIL3) was associated with increased risk of MI in humans. Here, we report elevated myocardial NEIL3 expression in heart failure patients and marked myocardial upregulation of Neil3 following MI in mice, especially in a fibroblast-enriched cell fraction. Neil3-/- mice showed increased mortality after MI compared to WT, caused by myocardial rupture. Neil3-/- hearts displayed enrichment of mutations in genes involved in mitogenesis of fibroblasts and transcriptome analysis revealed dysregulated fibrosis. Correspondingly, proliferation of vimentin+ and aSMA+ (myo)fibroblasts was increased in Neil3-/- hearts following MI. We propose that NEIL3 operates in genomic regions crucial for regulation of cardiac fibroblast proliferation and thereby controls extracellular matrix modulation after MI. Overall design: RNA from infarcted and non-infarcted LV of WT and Neil3-/- C57BL/6 mice obtained three days after induced myocardial infarction were subjected to RNA sequencing using Illumina Hiseq 2000
NEIL3-Dependent Regulation of Cardiac Fibroblast Proliferation Prevents Myocardial Rupture.
Age, Specimen part, Cell line, Subject
View Samples