Tanning is a skin protection mechanism against UV radiation. Pigment production initiates hours after exposure, and the mechanism controlling this delay was unknown. Here we reveal a skin UV-protection timer, governed by damped oscillatory dynamics of the melanocyte master regulator, MITF, which after UV exposure, synchronizes regulatory programs, first cell survival and later pigmentation. Remarkably, the same amount of UV dosage resulted in higher pigmentation of human skin when given every-other day compared to daily exposure. Daily UV exposure appears to perturb MITF dynamics, thus re-ordering the survival and pigmentation programs. This demonstrates that the skin is more sensitive to frequency than quantity of UV exposure. Mathematical modeling identified a double negative regulatory loop involving HIF1a and microRNA-148a that regulates MITF dynamics. Our study suggests evolutionary leverage of the UV-protection timer, as it evolved to induce maximum protection with minimum damage for the reduction of skin cancer risk.
UV-Protection Timer Controls Linkage between Stress and Pigmentation Skin Protection Systems.
Time
View SamplesChronic alcohol consumption can lead to alchohol-related brain damage (ARBD). Despite the well known acute effects of alcohol the mechanism responsible for chronic brain damage is largely unknown. Pathologically the major change is the loss of white matter while neuronal loss is mild and restricted to a few areas such as the prefrontal cortex. In order to improve our understanding of ARBD pathogenesis we used microarrays to explore the white matter transcriptome of alcoholics and controls.
Comorbidities, confounders, and the white matter transcriptome in chronic alcoholism.
Specimen part, Disease, Disease stage
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Controlled reoxygenation cardiopulmonary bypass is associated with reduced transcriptomic changes in cyanotic tetralogy of Fallot patients undergoing surgery.
Specimen part
View SamplesTo determine cardiac transcription profile in cyanotic Tetralogy of Fallot patients subjected to conrolled reoxygenation cardiopulmonary bypass, we collected myocardial samples at the end of the ischemic time. The transcriptional profile of the mRNA in these samples was measured with gene array technology
Controlled reoxygenation cardiopulmonary bypass is associated with reduced transcriptomic changes in cyanotic tetralogy of Fallot patients undergoing surgery.
Specimen part
View SamplesTo determine cardiac transcription profile in cyanotic Tetralogy of Fallot patients subjected to hyperoxic/standard cardiopulmonary bypass, we collected myocardial samples at the end of the ischemic time. The transcriptional profile of the mRNA in these samples was measured with gene array technology
Controlled reoxygenation cardiopulmonary bypass is associated with reduced transcriptomic changes in cyanotic tetralogy of Fallot patients undergoing surgery.
Specimen part
View SamplesTamoxifen (Nolvadex) is one of the most widely used and effective therapeutic agent for breast cancer. It benefits nearly 75% of patients with ER-positive breast cancer that receive this drug. Its effectiveness is mainly attributed to its capacity to function as an estrogen receptor (ER) antagonist, blocking estrogen binding sites on the receptor, and inhibiting the proliferative action of the receptor-hormone complex. Although, tamoxifen can induce apoptosis in breast cancer cells via upregulation of pro-apoptotic factors, it can also promote uterine hyperplasia in some women. Thus, tamoxifen as a multi-functional drug could have different effects on cells based on the utilization of effective concentrations or availability of specific co-factors. Evidence that tamoxifen functions as a GPR30 (G-Protein Coupled Receptor 30) agonist activating adenylyl cyclase and EGFR (Epidermal Growth Factor Receptor) intracellular signaling networks, provides yet another means of explaining the multi-functionality of tamoxifen. Here ordinary differential equation (ODE) modeling, RNA sequencing and real time qPCR analysis were utilized to establish the necessary data for gene network mapping of tamoxifen-stimulated MCF-7 cells, which express the endogenous ER and GPR30. The gene set enrichment analysis and pathway analysis approaches were used to categorize transcriptionally upregulated genes in biological processes. Of the 2,713 genes that were significantly upregulated following a 48 h incubation with 250 µM tamoxifen, most were categorized as either growth-related or pro-apoptotic intermediates that fit into the Tp53 and/or MAPK signaling pathways. Collectively, our results display that the effects of tamoxifen on the breast cancer MCF-7 cell line are mediated by the activation of important signaling pathways including Tp53 and MAPKs to induce apoptosis. Overall design: Gene expression analysis between tamoxifen-treated MCF-7 cells and untreated MCF-7 cells.
Tamoxifen-Induced Apoptosis of MCF-7 Cells via GPR30/PI3K/MAPKs Interactions: Verification by ODE Modeling and RNA Sequencing.
Cell line, Subject
View SamplesTo determine the changes in intra-renal gene expression in a novel large animal model of post Cardiopulmonary Bypass (CPB) acute kidney injury, we collected renal medulla samples obtained 24hours post intervention.
Changes in renal medulla gene expression in a pre-clinical model of post cardiopulmonary bypass acute kidney injury.
Specimen part, Treatment
View SamplesDamage-associated molecular pattern (DAMP) molecules S100A8 and S100A9 with well-known functions in inflammation, tumor growth and metastasis. It has been found to have promote tumor cell proliferation activity at low concentration . However, the mechanism underlying this remains unclear. In the current study, we performed genome expression profiling analysis using the Affymetrix genome wide microarray system to identify broad scale changes in gene expression associated with S100a8 or S100a9 recombinant protein stimulation in murine colon carcinoma cell line CT26.WT.
Inflammation-induced S100A8 activates Id3 and promotes colorectal tumorigenesis.
Cell line
View SamplesMorphogenesis of the mammary gland relies on the precise developmental control of morphological elements including TEBs, ducts and lobules. In the peripubertal mammary gland, rising levels of ovarian hormones control this development through a tightly controlled genetic program where specific sets of genes are up-regulated.
In utero and lactational exposure to vinclozolin and genistein induces genomic changes in the rat mammary gland.
Specimen part, Treatment
View SamplesThe intestinal epithelium constitutes a crucial defense to the potentially life-threatening effects of gut microbiota. However, due to a complex underlying vasculature, hypoperfusion and resultant tissue ischemia pose a particular risk to function and integrity of the epithelium. The small ubiquitin-like modifier (SUMO) conjugation pathway critically regulates adaptive responses to metabolic stress and is of particular significance in the gut, as inducible knockout of the SUMO-conjugating enzyme Ubc9 results in rapid intestinal epithelial disintegration. Here we analyzed the pattern of individual SUMO isoforms in intestinal epithelium and investigated their roles in intestinal ischemia/reperfusion (I/R) damage. Immunostaining revealed that epithelial SUMO2/3 expression was almost exclusively limited to crypt epithelial nuclei in unchallenged mice. However, intestinal I/R or overexpression of Ubc9 caused a remarkable enhancement of epithelial SUMO2/3 staining along the crypt-villus axis. Unexpectedly, a similar pattern was found in SUMO1 knockout mice. Ubc9 transgenic mice, but also SUMO1 knockout mice were protected from I/R injury as evidenced by better preserved barrier function and blunted inflammatory responses. PCR array analysis of microdissected villus-tip epithelia revealed a specific epithelial contribution to reduced inflammatory responses in Ubc9 transgenic mice, as key chemotactic signaling molecules such as IL17A were significantly downregulated. Together, our data indicate a critical role particularly of the SUMO2/3 isoforms in modulating responses to I/R and provide the first evidence that SUMO1 deletion activates a compensatory process that protects from ischemic damage.
Ubc9 overexpression and SUMO1 deficiency blunt inflammation after intestinal ischemia/reperfusion.
Treatment
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