Indoxyl sulfate (IS) is a uremic toxin and ligand of the aryl-hydrocarbon receptor (Ahr), a transcriptional regulator. Elevated serum IS may contribute to the progression of kidney disease. Therefore, we assessed mouse podocyte damage mediated by IS. Ahr was predominantly localized to the podocyte nucleus in vivo and in vitro. In isolated glomeruli, IS-exposure for 2 24 h induced Cyp1a1 expression, the most sensitive biomarker of Ahr activation. Mice exposed to IS for 48 weeks exhibited microalbuminuria, and mild glomerular injury characterized by ischemic changes, partial podocyte foot process effacement, as well as vascular and tubulointerstitial damage. Chronically IS-exposed kidneys exhibited decreased mRNA, decreased protein levels, and altered staining patterns for podocin, synaptopodin, and non-muscle myosin IIA (Myh9). Immortalized podocytes, upon differentiation, exhibited Ahr nuclear translocation beginning 30 min after 1 mM IS-exposure. At 2 h, there was a dose-dependent decrease in podocyte mRNA expression of WT1, Podxl, Snypo, Myh9, Actn4, and Cd2ap. After 24 h of exposure to IS, podocytes were smaller, had fewer actin/Myh9 fibers, and decreased viability. Ahr-RNAi decreased mRNA expression of podocyte-specific proteins and inhibited Cyp1a1 induction by IS-exposure. Combinations of Ahr-RNAi and IS-exposure further decreased Myh9 expression. In immortalized human podocytes, IS treatment caused cell injury, decreased mRNA expression of podocyte-specific proteins, integrins, collagens, cytoskeletal proteins, and bone morphogenetic proteins, and increased cytokine and chemokine expression. Thus, chronic IS-exposure causes glomerular damage by activating Ahr, altering podocyte function, differentiation, and morphology, and inducing a pro-inflammatory phenotype.
Podocyte injury caused by indoxyl sulfate, a uremic toxin and aryl-hydrocarbon receptor ligand.
Specimen part, Treatment
View SamplesWe report transcriptome of Klf9-OE PGC by RNA-seq Overall design: RNA-seq of Klf9-OE clutured for one day in bFGF containing GS medium by using Illumina HiSeq2500.
Identification of KLF9 and BCL3 as transcription factors that enhance reprogramming of primordial germ cells.
Specimen part, Subject
View SamplesHuman pluripotent stem cells (hPSCs) such as embryonic stem cells and induced pluripotent stem cells are promising materials for cell-based regenerative therapies to heart diseases. However, until realization there are many hurdles such as high efficiency of cardiac differentiation of hPSCs and production of clinical-grade cardiac cells derived from hPSCs. Here, we show that a novel small molecule KY02111 robustly enhances differentiation to functional cardiomyocytes from hPSCs.
A small molecule that promotes cardiac differentiation of human pluripotent stem cells under defined, cytokine- and xeno-free conditions.
Specimen part, Cell line
View SamplesClassic ‘position effect’ experiments repositioned genes to the telomere to demonstrate that the epigenetic landscape can dramatically alter gene expression. Here we show that systematic gene knockout collections provide an exceptional resource for interrogating position effects, not only at the telomere but at every single genetic locus. Because deleted genes are replaced by the same reporter gene, interrogation of this reporter provides a sensitive probe into many different chromatin environments while controlling for genetic context. Using this approach we find that, whereas replacement of yeast genes with the kanMX marker does not perturb the chromatin landscape, differences due to gene position account for more than 35% of marker gene activity. We observe chromatin influences different from those reported previously, including an antagonistic interaction between histone H3 lysine 36 trimethylation (H3K36me3) and the Rap1 transcriptional activation site in kanMX that is mediated through a Set2-Rpd3-dependent pathway. This interaction explains why some yeast genes have been resistant to deletion and allows successful generation of these deletion strains using a modified transformation procedure. These findings demonstrate that chromatin regulation is not governed by a uniform ‘histone code’, but by specific interactions between chromatin and genetic factors. Overall design: Data included are RNA-Seq data for 4 heterzygous diploid yeast strains and diploid wild-type. Therea re three replicates for each heterzygous strain, and six replicates for wild-type.
Decoupling epigenetic and genetic effects through systematic analysis of gene position.
Subject
View SamplesRett syndrome (RTT) is a devastating neurodevelopmental disorder that occurs once in every 10,000-15,000 live female births. Despite intensive research, no effective cure is yet available. Valproic acid (VPA) has been used widely to treat mood disorder, epilepsy, and a growing number of other disorders. In limited clinical studies, VPA has also been used to control seizure in RTT patients with promising albeit somewhat unclear efficacy. In this study we tested the effect of VPA on the neurological symptoms of RTT and discovered that short-term VPA treatment during the symptomatic period could reduce neurological symptoms in RTT mice. We found that VPA restores the expression of a subset of genes in RTT mouse brains, and these genes clustered in neurological disease and developmental disorder networks. Our data suggest that VPA could be used as a drug to alleviate RTT symptoms.
VPA alleviates neurological deficits and restores gene expression in a mouse model of Rett syndrome.
Specimen part
View SamplesRegulation of spatiotemporal gene expression in higher eukaryotic cells is critical for the precise and orderly development of undifferentiated progenitors into committed cell types of the adult. Recently, dynamic epigenomic regulation, including chromatin remodeling and histone modifications by transcriptional coregulator complexes, has been shown to be involved in transcriptional regulation. Precisely how these coregulator complexes exert their cell-type and developing stage-specific activity is largely unknown. In this study, we aimed to isolate the histone demethylase LSD1 complex from neural cells by biochemical purification. In so doing, we identified MyT1 as a novel LSD1 complex component. MyT1 is a neural cell-specific zinc finger factor and it forms a stable multiprotein complex with LSD1 through direct interaction. Target gene analysis using microarray and ChIP assays revealed several genes, including PTEN, that were directly regulated by the LSD1-MyT1 complex. Knockdown of either LSD1 or MyT1 derepressed the expression of endogenous target genes and inhibited cell proliferation of a neuroblastoma cell line, Neuro2a. We propose that formation of tissue-specific combinations of coregulator complexes is a critical mechanism for tissue-specific transcriptional regulation.
Identification of myelin transcription factor 1 (MyT1) as a subunit of the neural cell type-specific lysine-specific demethylase 1 (LSD1) complex.
Cell line, Treatment
View SamplesMice with homozygous null mutations in the HDL receptor (SR-BI) and apoE genes (SR-BI KO/apoE double KO (dKO) mice) spontaneously develop occlusive, atherosclerotic coronary artery disease (CAD) and die prematurely (50% mortality at 42 days of age) on standard chow diet feeding. Microarray analysis was performed to investigate the changes in gene expression profiles during the development of spontaneous severe CAD, which includes myocardial infarction and heart failure. These data will provide new insights in understanding the pathophysiology of CAD.
Identification of apolipoprotein D as a cardioprotective gene using a mouse model of lethal atherosclerotic coronary artery disease.
Age, Specimen part
View SamplesPrenatal exposure to valproic acid, an established anti-epileptic drug, has been reported to impair postnatal cognitive function of children from epileptic mothers. Nevertheless, its pathology and proper treatment to minimize the effects remain unknown. In mice, we found that the postnatal cognitive function impairment was mainly caused by a reduction of adult neurogenesis and abnormal neuronal features in the hippocampus, which could be ameliorated by voluntary running.
Reduced Adult Hippocampal Neurogenesis and Cognitive Impairments following Prenatal Treatment of the Antiepileptic Drug Valproic Acid.
Sex, Specimen part, Treatment
View SamplesThe major antioxidant glutathione (GSH) protects cancer cells from oxidative damage leading to ferroptosis, an iron-dependent cell death. Therapy-resistant cancer cells often manifest high expression of the cystine-glutamate antiporter subunit xCT which enhances cystine uptake leading to GSH synthesis and thereby survive oxidative damage and ferroptosis. The use of GSH-depleting agents including xCT inhibitors might thus be expected to enhance the efficacy of cancer therapy. On the other hand, the efficacy of xCT-targeted therapy depends on the cellular metabolism affecting antioxidant system in cancer cells and metabolic reprograming might reduce the efficacy of cancer therapy using xCT inhibitors. Recently, to overcome the resistance to xCT-targeted therapy, we performed a library screening and identified an oral anesthetics dyclonine (DYC) as a sensitizing drug for xCT inhibitor sulfasalazine (SSZ). However, DYC is a local anesthetic and might not suitable for the systemic administration combined with SSZ in a clinical setting. In this study, we identified a vasodilator oxyfedrine (OXY) which is clinically used in systemic administration also acts as a sensitizing drug to GSH-depleting agents in multiple type of cancer cells. OXY and DYC share the motif required for the covalent inhibition of aldehyde dehydrogenases (ALDHs), and combined treatment with OXY and SSZ induced the accumulation of cytotoxic aldehyde 4-hydroxynonenal (4-HNE) and induce cell death in SSZ-resistant cancer cells. Furthermore, we found that OXY sensitizes cancer cells to radiation therapy which decreases intracellular GSH content. Our findings establish a rationale for repurposing of OXY as a sensitizing drug for xCT-targeted cancer therapy.
Vasodilator oxyfedrine inhibits aldehyde metabolism and thereby sensitizes cancer cells to xCT-targeted therapy.
Specimen part
View SamplesTo identify the possible targets in EMT-acquisition after developing acquired platinum resistance in urothelial carcinoma (UC), we examined the changes in global gene expression before and after development of acquired platinum resistance. Comparing two types of acquired platinum resistant UC cells and their corresponding parent cells, in the end we identified 49 genes (25 up-regulated and 24 down-regulated genes) which were commonly changed in two acquired platinum resistant UC cells.
Acquired platinum resistance involves epithelial to mesenchymal transition through ubiquitin ligase FBXO32 dysregulation.
Specimen part
View Samples