Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Ischemic vs. nephrotoxic acute renal failure, early time points (2h and 8h)

ABSTRACT: Acute renal failure (ARF) has high morbidity and mortality. In animal ARF models, effective treatments must be administered before or shortly after the insult, limiting their clinical potential. We used microarrays to identify early biomarkers that distinguish ischemic from nephrotoxic ARF, or that detect both injury types. We compared rat kidney transcriptomes 2 and 8 hours after ischemia/reperfusion and after mercuric chloride. Quality control and statistical analyses were necessary to normalize inter-experimental groups, eliminate outliers, and exclude unaltered genes. Principal component analysis revealed distinct ischemic and nephrotoxic trajectories, and clear array groupings. Therefore, we used supervised analysis, t-tests and fold changes, to compile gene lists for each group, exclusive or non-exclusive, alone or in combination. We used two lots of microarrays (Lot 1, n = 24, Lot 2, n = 12), for a total of 36 microarrays. Five of them were duplicates, where two aliquots of RNA from the same rat were processed independently and hybridized to separate microarrays. Normal rats were used in both lots (n = 3 for each lot) for normalization.

ORGANISM(S): Rattus norvegicus

SUBMITTER: Peter Yuen

PROVIDER: E-GEOD-3219 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Publications

Ischemic and nephrotoxic acute renal failure are distinguished by their broad transcriptomic responses.

Yuen Peter S T PS Jo Sang-Kyung SK Holly Mikaela K MK Hu Xuzhen X Star Robert A RA

Physiological genomics 20060228 3

Acute renal failure (ARF) has a high morbidity and mortality. In animal ARF models, effective treatments must be administered before or shortly after the insult, limiting their clinical potential. We used microarrays to identify early biomarkers that distinguish ischemic from nephrotoxic ARF or biomarkers that detect both injury types. We compared rat kidney transcriptomes at 2 and 8 h after ischemia/reperfusion and after mercuric chloride. Quality control and statistical analyses were necessary ...[more]

PMID: 16507785

Similar Datasets

Project description:Fibroblasts are present in every organ. While the role fibroblasts in chronic diseases such as fibrosis or tumor expression has been extensively explored, little is known about their physiological role. The kidney possesses a unique capacity to recover from even severe acute injury. We study molecular mechanisms of this intrinsic repair capacity in the mouse model of ischemia-reperfusion (IR). In this model, the renal artery and vein are clamped for 45 min, leading to acute kidney injury. The kidney spontaneously recovers from such IR injury within 14 days. IR kidney injury is associated with a transient accumulation of fibroblasts in the diseased tissue. We hypothesized that fibroblasts aid the repair of acute IR injury in the kidney. To elucidate how FSP1+ fibroblasts may contribute to the repair of kidney injury, we undertook a global unbiased approach to compare gene expression profiles of fibroblasts isolated from kidneys post-IRI and from control kidneys by FACS sorting. To investigate the role fibroblasts may play in the repair of kidney inhury, we performed ischemia reperfusion injury surgery on transgenic mice in which the FSP-1 promoter drives EGFP expression. Kidney injury peaks at day 3 post-IRI, followed by spontaneous regeration that restores nearly perfect kidney architecture and health by day 10. Fibroblasts are thought to possibly play a role in this process, as they are normally rare in the healthy kidney, acute kidney injury is associated with a transient accumulation of interstitial fibroblasts, but whether they may help repair the acute kidney injury or in fact could contribute to the damage is not known. To compare the gene expression profiles of normal fibroblasts and those from post-ischemic kidneys, we sacrificed control FSP1-GFP mice and the FSP1-GFP mice three days post-IRI. We generated single-cell suspensions from both the post-IRI and control kidneys, and then isolated FSP1-GFP+ cells by FACS sorting that, when cultured on plastic, displayed typical fibroblast morphology. Total RNA was immediately extracted from the sorted cells and amplified to produce enough for a array. We biotinylated five of the samples from post-ischemic kidneys and three of the control (non-ischemic) kidneys and used Affymetrix 3' Arrays to examine differences in gene expression profiles between the two groups that may she some light on what role, if any, fibroblasts play in the spontaneous healing of the kidney after acute kidney injury. We performed ischemia reperfusion surgery in FSP1-GFP mice, and at day 3, we sacrificed the mice, isolated FSP1-GFP positive cells from both IR and normal control kidneys by FACS sorting, extracted total RNA from the isolated FSP1-GFP cells and used Affymetrix Mouse Expression Array 430 2.0 microarrays to perform gene expression profiling of the samples. All told, we performed the FACS Sorting, RNA extration, and hybridization with 5 ischemic kidneys and 3 normal kidneys. Fibroblasts, acute kidney injury, repair, comparative gene expression profiling, microarrays, FACS sorting, role in healing

Project description:Coronary heart disease is the leading cause of death worldwide. After an acute myocardial infarction, early reperfusion reduces infarct size, which correlates with improved clinical outcomes. Paradoxically, reperfusion although relieving ischemia, accelerates apoptosis in injured cardiomyocytes, which has led to the view that myocardial salvage is futile beyond the first few hours of reperfusion. In murine hearts subjected to 90 min of coronary artery occlusion and then 48 h of reperfusion, we show transient activation of intrinsic prosurvival insulin-like growth factor-1 (IGF-1) signaling. In these hearts, acute IGF-1 receptor inhibition decreases the abundance of prosurvival signaling molecules, and markedly activates caspase-3, a potent effector of apoptosis, in infarct border zone cardiomyocytes. We found that mouse mast cell protease-4 (MMCP-4) degraded IGF-1 in vitro by a novel catalytic activity of chymases. In vivo, this degradation, which is triggered by mast cell infiltration into the peri-infarct region and MMCP-4 extravasation, between 48 and 72 h post-ischemia/reperfusion (I/R), attenuates IGF-1 prosurvival signaling. In MMCP-4-deficient mice, while infarct size is not reduced at 24 h post-I/R, at 72 h post-I/R myocardial IGF-1 levels and signaling are increased, resulting in activation of the survival kinases Akt and ERK, inhibition of caspase-3, and reduced myocardial cell death. As a consequence, I/R-mediated loss of viable myocardium, adverse cardiac remodeling and contractile impairment are markedly reduced. Cardiomyocyte survival with consequent myocardial salvage may thus be possible even days after an ischemic insult, making them a novel therapeutic target for delayed cardioprotective therapy. Group 1 is wild type C57Bl6 uninjured hearts. These mice were not undergone any surgery and used as controls. Group 2 are wild type C57Bl6 72 h post-ischemia reperfusion (IR) injury hearts. These mice for subjected to ischemia reperfusion (IR) involving 90 min of left anterior descending coronary artery occlusion followed by reperfusion for 3 days or 72 h.

Project description:Experimental Design: 1. The goal of the experiment: Age-Dependent Gene Expression Profiles After Hepatic Ischemia/Reperfusion: Implications for the AP-1 and Ubiquitin-Proteosome Pathways 2. Brief description of the experiment: Hepatic ischemia/reperfusion (I/R) injury is a complication of liver surgery, transplantation and shock. Our previous studies have suggested there is an age-dependent response to I/R. In the present study, we examined global gene expression after liver I/R in young (4-5 weeks) and adult (12-14 months) mice using Affymetrix microarray. Gene expression was filtered based on a change in expression of 1.5-fold relative to respective controls and then analyzed by ANOVA. Seventy-two genes in young mice and 56 genes in adult mice had significantly increased expression. Of these, only 18 were up-regulated in both age groups. In young mice, 289 genes were down-regulated whereas in adult mice, 874 genes were decreased. Of these genes, 175 genes were decreased in both groups. Pathway and network analyses of up- and down-regulated gene lists revealed a number of notable differences between young and adult mice. Of these, we found that genes related to the activating protein-1 (AP-1) pathway were upregulated preferentially in young mice. This corresponded with an increase in AP-1 activation in young versus adult mice. Finally, we found that genes related to the ubiquitin-proteasome pathway were selectively down-regulated in adult mice. This was accompanied by reduced degradation of the inhibitory protein, I?B?, in adult mice. The data demonstrate specific, pathway- and network-related differences in gene expression profiles between young and adult mice in the response to I/R. More specifically, we have identified two pathways that may contribute to the superior response to I/R in young mice which represent potential therapeutic targets. Keywords: treated vs non treated 2 age groups of 6 young and 6 adult mice that underwent either 90 minutes of partial ischemia followed by 1 hour of reperfusion (n=3) or sham operation (n=3) We used microarray to uncover the genomic response after ischemia reperfusion in 2 different age groups

Dataset Information

Ischemic vs. nephrotoxic acute renal failure, early time points (2h and 8h)

Publications

Ischemic and nephrotoxic acute renal failure are distinguished by their broad transcriptomic responses.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets