Project description:Here, we present the first study showing race and side-specific differences in the trajectories of epigenetic aging in normal colonic mucosa. The cohort conisted of matched biopsies of left/right colon from healthy individuals (n=129). The majority of individuals were African American (n=89). Methylation arrays (Illumina EPIC) were performed on DNA extracted from fresh frozen biopsies taken at the time of colonoscopy. Our results provide novel insight of epigenetic aging underlying racial disparities in CRC. Side-specific colonic epigenetic aging may be a promising marker to guide interventions to reduce CRC burden.
Project description:There are well-documented racial differences in age-of-onset and laterality of colorectal cancer. Epigenetic age acceleration is postulated to be an underlying factor. However, comparative studies of side-specific colonic tissue epigenetic aging are lacking. Here, we performed DNA methylation analysis of matched right and left biopsies of normal colon from 128 individuals. Among African Americans (n = 88), the right colon showed accelerated epigenetic aging as compared to individual-matched left colon (1.51 years; 95% CI = 0.62 to 2.40 years; two-sided P = .001). In contrast, among European Americans (n = 40), the right colon shows remarkable age deceleration (1.93 years; 95% CI = 0.65 to 3.21 years; two-sided P = .004). Further, epigenome-wide analysis of DNA methylation identifies a unique pattern of hypermethylation in African American right colon. Our study is the first to report such race and side-specific differences in epigenetic aging of normal colon, providing novel insight into the observed younger age-of-onset and relative preponderance of right-side colon neoplasia in African Americans.
Project description:The entorhinal cortex of the mouse seems to be sensitive to molecular mechanisms that have been linked to the pathology of Alzheimer's disease. In this microarray study we are interested in comparing the expression profile of the left versus the right EC of the mouse, in order to understand if there is a significant difference in gene expression that might reveal any insights into the differential activation of these areas. We used microarrays to detail the global programme of gene expression underlying a possible lateralization of the EC in the mouse brain (left versus right EC). The left and the right entorhinal cortices of 6 month-old C57BL/6 wild-type mice was dissected out by following anatomical landmarks and guided by the Mouse Brain Paxinos and Franklin’s atlas. Samples were immediately processed for RNA extraction by using the RNeasy Kit from QIAGEN according to manufacturer’s instructions. Before running the microarrays, RNA quality and integrity was monitored on an Agilent BioAnalyzer. Samples were then run on Affymetrix Genechip Mouse gene 2.0 ST arrays following Affymetrix’s standard procedures (n=3 per cortical hemisphere). Microarrays data were analyzed through the use of Ingenuity® iReport (Ingenuity® Systems, www.ingenuity.com).
Project description:The entorhinal cortex of the mouse seems to be sensitive to molecular mechanisms that have been linked to the pathology of Alzheimer's disease. In this microarray study we are interested in comparing the expression profile of the left versus the right EC of the mouse, in order to understand if there is a significant difference in gene expression that might reveal any insights into the differential activation of these areas. We used microarrays to detail the global programme of gene expression underlying a possible lateralization of the EC in the mouse brain (left versus right EC).
Project description:In our study, we obtained paired normal left-sided and right-sided colon mucosa tissues by colonoscopy, and 9,642 individual cells were analyzed by single-cell RNA-seq, which aims to explore the differennces of cell component between the left and the right colon.
Project description:Several inherited arrhythmias primarily affect the right ventricle, including Brugada syndrome and arrhythmogenic cardiomyopathy, however the molecular basis of this chamber predilection is not well understood. Right and left ventricular cardiomyocytes derive from distinct progenitor populations. Here, we show that Hrt2, a gene associated with Brugada syndrome, is a direct target of Wnt signaling in the right ventricle and Notch signaling in the left ventricle. Perturbations of Wnt and Notch signaling during development and in the adult lead to chamber-specific transcriptional effects on Hrt2 expression associated with distinct binding patterns to Hrt2 enhancers. Differential enhancer binding is present at early developmental stages when the signaling pathways are active and persists into adulthood. Consistent with chamber-specific regulation, mice deficient in Wnt transcriptional activity dysregulate only a small fraction of transcripts in common between ventricles. Wnt target gen es important for cellular electrophysiology are differentially regulated, resulting in perturbed cardiac conduction and cellular electrophysiological parameters only within the right ventricle. Ex vivo and in vivo physiologic stimulation of the right ventricle is sufficient to induce ventricular tachycardia in Wnt transcriptionally inactive hearts, while left ventricular stimulation has no effect. Taken together, these data delineate mechanisms underlying ventricular-specific arrhythmia susceptibility due to embryonic programming.
Project description:Several inherited arrhythmias primarily affect the right ventricle, including Brugada syndrome and arrhythmogenic cardiomyopathy, however the molecular basis of this chamber predilection is not well understood. Right and left ventricular cardiomyocytes derive from distinct progenitor populations. Here, we show that Hrt2, a gene associated with Brugada syndrome, is a direct target of Wnt signaling in the right ventricle and Notch signaling in the left ventricle. Perturbations of Wnt and Notch signaling during development and in the adult lead to chamber-specific transcriptional effects on Hrt2 expression associated with distinct binding patterns to Hrt2 enhancers. Differential enhancer binding is present at early developmental stages when the signaling pathways are active and persists into adulthood. Consistent with chamber-specific regulation, mice deficient in Wnt transcriptional activity dysregulate only a small fraction of transcripts in common between ventricles. Wnt target gen es important for cellular electrophysiology are differentially regulated, resulting in perturbed cardiac conduction and cellular electrophysiological parameters only within the right ventricle. Ex vivo and in vivo physiologic stimulation of the right ventricle is sufficient to induce ventricular tachycardia in Wnt transcriptionally inactive hearts, while left ventricular stimulation has no effect. Taken together, these data delineate mechanisms underlying ventricular-specific arrhythmia susceptibility due to embryonic programming.
Project description:We report the mRNA sequencing of right and left atria from an adult inducible, cardiomyocyte-specific Notch gain-of-function mouse model (iNICD). Using the tetracycline-on system, we activated Notch by feeding doxycycline chow for 3 weeks to mice that were at least 8 weeks old. We asked what transcriptional changes occur in right versus left atrial cardiomyocytes in response to the same stimulus (Notch signaling). mRNA sequencing on separated right and left atria revealed that there are more differentially dysregulated transcripts (1,011) than similarly regulated transcripts (447) in the right and left atria, which is a simiar paradigm as what occurs in human atrial cardiomyocytes of patients with atrial fibrillation.