MicroRNAs profiles of contrast-induced acute kidney injury rats
ABSTRACT: Contrast-induced acute kidney injury (CI-AKI) is typically defined by an increase in serum creatinine (SCr) after intravascular administration of contrast medium. Since creatinine is an unreliable indicator for acute changes in kidney function, an early biomarkers for CI-AKI diagnosis is important for initiating therapy.We assessed the hypothesis that circulating microRNAs (miRNAs) could be served as potential biomarkers to early detect CI-AKI.The rat model of acute kidney injury was developed as we previously described. We first detect miRNA profile of plasma and kidney tissue using Agilent microarray platform. 3 miRNA species with > 1.5-fold increase in plasma samples of CI-AKI rats, including miRNA-30a, miRNA-30e and miRNA-188, were selected as candidate miRNAs of potential biomarkers. 24 rats were randomly divided into 2 groups (CI-AKI group and control group), each with 4 subgroups (n=3). Peripheral blood and kidney samples were harvest at 8h after contrast medium/normal saline administration. Total RNA sample from each rat in the same subgroup was combined together as pooled sample for further test. The Agilent microarray platform was adapted to profile the miRNA spectra.
Project description:In the present study, goal was to scan the potential biomarker for acute kidney injury induced by aristolochic acid I (AAI).We utilized the microarry analysis to investigate the microRNA (miRNA) expression profile in kidneys from rat treated by 40mg/kg AA I for 2-6 days. miRNAs with significantly different expression of global miRNA expression profile were validated by qRT-PCR. For miRNAs still significantly disregulation, we further examined the expression in plasma of rats treated with AAI dosed at 10, 20 and 40mg/kg AAI for 2-6 days by qRT-PCR. miRNAs with significantly dysregulation in plasma, their expression in brain, liver and heart was examined for kicking out the non-specific disregulation in AAI induced acute kidney injury, so that the significant dysregulation miRNAs with specificity in kidney and plasma was found as potential biomarkers for AAI induced acute kidney injury. Five control and 15 kidneys treated with 40mg/kg AAI on day 2, 4 and 6 was examined by microarray.
Project description:Drug resistance, caused by complex and redundant mechanisms, is a major obstacle in cancer treatment, especially in liver and kidney cancers. Combinational therapy of miRNAs, which concurrently target multiple pathways, with anticancer drugs represent a new strategy to improve the drug response. By a systems approach, we identified that miR-27b, a miRNA deleted in liver and kidney cancers, sensitizes cancer cells to a broad spectrum of anticancer drugs in vitro and in vivo. Two samples transfected with nontarget miRNA control or miR-27b mimics followed by 48 hours doxorubicin treatment
Project description:Contrast-induced acute kidney injury (CI-AKI) is typically defined by an increase in serum creatinine after intravascular administration of contrast medium. Because creatinine is an unreliable indicator of acute changes in kidney function, we assessed whether circulating microRNAs (miRNAs) could serve as biomarkers for early detection of CI-AKI.Using a rat model of CI-AKI, we first evaluated the miRNA profile of rat plasma and kidney. Three miRNA species with >1.5-fold increase in plasma samples of CI-AKI rats, including miRNA-188, miRNA-30a, and miRNA-30e, were selected as candidate miRNAs. Quantitative real-time polymerase chain reaction showed that these candidate miRNAs peaked in concentration around 4 hours after contrast medium exposure and were relatively renal-specific. We compared the plasma levels of these candidate miRNAs in 71 patients who underwent coronary angiography or percutaneous coronary intervention and developed CI-AKI with those of 71 matched controls. The plasma levels of the 3 candidate miRNAs were significantly elevated in the CI-AKI group as compared to the control group. Receiver operating characteristic analysis showed that these miRNAs significantly distinguished patients with CI-AKI from those without CI-AKI. MiRNA composites were highly accurate for CI-AKI prediction, as shown in maximized specificity by treble-positive miRNA composite or maximized Youden index by any-positive miRNA composite. Moreover, the selected miRNAs changes were associated with Mehran Risk Scores.Plasma levels of candidate miRNAs significantly distinguished patients with CI-AKI from those without CI-AKI. Thus, miRNAs are potential biomarkers for early detection of CI-AKI.
Project description:MicroRNAs (miRNAs) expression profiles are widely investigated in the major cancers, but their specific roles and functions in cancers have not yet to be fully elucidated. We investigated expression profiles of miRNAs in clear cell renal cell carcinomas (ccRCCs) and in matched normal kidney tissues (NCTs) by using a miRNAs microarray platform which covers a total of 851 human miRNAs. Tumor tissue samples were immediately snap-frozen in liquid nitrogen after surgery, and then stored in a deep freezer at -80°C. Total RNA was extracted from 5 ccRCC tissues and paired NCTs and expression profiles of miRNAs were screened by using a miRNA microarray platform.
Project description:Microarray analysis of human kidneys with acute kidney injury (AKI) has been limited because such kidneys are seldom biopsied. However, all kidney transplants experience AKI, and early kidney transplants without rejection are an excellent model for human AKI: they are screened to exclude chronic kidney disease, frequently biopsied, and have extensive follow-up. We used histopathology and microarrays to compare indication biopsies from 28 transplants with AKI to 11 pristine protocol biopsies of stable transplants. Kidneys with AKI showed increased expression of 394 injury-repair response associated transcripts, including many known epithelial injury molecules (e.g. ITGB6, LCN2), tissue remodeling molecules (e.g. VCAN), and inflammation molecules (S100A8, ITGB3). Many other genes also predict the phenotype, depending on statistical filtering rules, including AKI biomarkers as HAVCR1 and IL18. Most mouse orthologs of the top injury-repair transcripts were increased in published mouse AKI models. Pathway analysis of the injury-repair transcripts revealed similarities to cancer, development, and cell movement. The injury-repair transcript score AKI kidneys correlated with reduced function, future recovery, brain death, and need for dialysis, but not future graft loss. In contrast, histologic features of "acute tubular injury" did not correlate with function or with the molecular changes. Thus the injury-repair associated transcripts represent a massive coordinate injury-repair response of kidney parenchyma to AKI, similar to mouse AKI models, and provide an objective measure for assessing the severity of AKI in kidney biopsies and validation for the use of many AKI biomarkers. AKI biopsies sample names and CEL files are from GSE21374. All consenting renal transplant patients undergoing biopsies for cause as standard of care between 09/2004 and 10/2007 at the university of Alberta or between 11/2006 and 02/2007 at the University of Illinois were included in the analysis. In addition to the cores required for standard histopathology, we collected one core for gene expression studies. the relationship between gene expression in the biopsy and subsequent graft loss was analyzed.
Project description:18 zero-hour and 18 selected post-transplant (Tx) biopsy samples from 18 kidney allografts (8 acute kidney injury (AKI), 10 PBx - protocol biopsies - controls) were analyzed by using the Affymetrix GeneChip® miRNA 3.0 Array. Comparison between control group (protocol biopsies) and indication biopsies with histological lesions of acute tubular necrosis without rejection (ATN).
Project description:The pathogenesis of contrast-induced acute kidney injury (CI-AKI) is incompletely understood. MicroRNAs (miRNAs) are important mediators that normally function via post-transcriptional degradation of target mRNAs. Emerging evidence indicates the appearance of differentially expressed (DE) miRNAs in CI-AKI following the injection of intravenous contrast medium. However, there are differences in the pathological mechanism and incidence of CI-AKI between intravenous and intra-arterial contrast administration. The present study aimed to investigate the critical roles of dysregulated miRNAs and their associated mRNAs in kidney injury following intra-arterial contrast medium exposure. Based on a reliable CI-AKI rat model, we conducted genome-wide miRNA and mRNA expression profiling analysis using deep sequencing. In the study, 36 DE mature miRNAs were identified (fold change > 1.5 and p value < 0.05) in the kidneys of CI-AKI rats (n = 3) compared with that in the controls (n = 3), consisting of 23 up-regulated and 13 down-regulated DE miRNAs. Bioinformatic analysis revealed that wingnut (Wnt), transforming growth factor beta (TGF-β), and 5'-AMP-activated protein kinase (AMPK) signaling pathways were most likely to be modulated by these dysregulated miRNAs. Around 453 dysregulated genes (fold change > 2.0 and p value < 0.05) were identified. Integrated analysis revealed 2037 putative miRNA-mRNA pairs with negative correlations. Among them, 6 DE miRNAs and 13 genes were selected for further quantitative real-time reverse transcription polymerase chain reaction validation (n = 6 for each group), and a good correspondence between the two techniques was observed. In conclusion, the present study provided evidence of miRNA-mRNA interactions in the development of kidney injury following an intra-arterial contrast injection. These findings provide insights into the underlying mechanisms of CI-AKI.
Project description:In deceased donor kidney transplantation, acute kidney injury (AKI) prioir to surgery is a major determinant of delayed graft function (DGF), but AKI is histologically silent and difficult to assess. We hypothesized that a molecular measurement of AKI would add power to conventional risk assessments to predict the early poor allograft function at first week post transplantation. We performed microarrays on implantation biopsies taken during reperfusion in 70 deceased donor kidneys from 53 donors. Early poor function was classified by two definitions on day 7 post-transplantation: serum creatinine greater than 265 umol/L (3 mg/dL) or the requirement for dialysis. Donor age and related risk scores (Irish, Schold, KDRI) associated with worse early function, as expected, but histologic features (glomerulosclerosis; pathology risk scores (Remuzzi, MAPI)) correlated with donor age but not with poor function. However, molecular AKI signal, previously defined in kidneys with early injury, was the best single predictor of poor allograft function. The combination of donor age and the AKI signal improved the prediction of poor function. In addition, asssessments of tissue quality particularly donor age, Banff ct, Irish and KDRI scores, showed negative correlative trend with late graft function, whereas the AKI signal did not. Thus donor age and the molecular AKI signal are the main predictors of early impaired function, but have little impact on survival.
Project description:Identifying the exact molecules associated with CRC metastasis may be crucial to understand the process, which might also be translated to the diagnosis and treatment of CRC. In this study, we investigate the association of microRNA expression patterns with the lymph node metastasis of colorectal cancer. To investigate the association of microRNA expression patterns with the lymph node metastasis of colorectal cancer, eight primary colorectal cancer tissues derived from stage II–III colorectal cancer patients with (n = 4) or without (n = 4) lymph node metastasis were collected and the miRNA expression profiles of them were determined using Agilent miRNA microarray. Different miRNA expression profiles were identified in CRC tissues between lymph node metastasis positive and negative group.
Project description:To investigate the gene expression profile of genamycin induced nephrotoxicity in a time-series aspect, SD rats were administrated once daily with saline, genamycin 80 mgkg for 28 consecutive days by intramuscular injection folled by 28 days recovery. Kidney samples were collected for microarray analysis and histological examination. There were 4360 and 4323 regulated genes for females and males, respectively, however, the overlapping expression genes coregluated at each time point were few, with 2 for females and 12 for males. By Principle Component Analysis and Hierarchical Cluster, the gene expression patterns were apparently associated with the disease stage of the nephrotoxicity,while GO Annotation showed the biological processes were specific to each course of this nephrotoxicity.Our studymapped the different gene expression patterns at the initiation, development and recovery stage of gentamycin-induced nephrotoxicity Gene expression in kidney from SD rats administrated once daily with saline or 80 mg/kg genamycin by intramuscular injection for 28 consecutive days follwed by 28 days recovery were measured using Aglient Rat Whole Genome 4*44 k array