Project description: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:The availability of mesenchymal stem cells in kidney injury repair has been demonstrated. However, the underlying molecular mechanism remains not well understood. Herein, we profiled the altered microRNAs in renal tissiues from cisplatin-induced acute kidney injury (AKI) rats administrated with or without rat bone marrow mesenchymal stem cells, normal kidneys as control. Sprague Dawley rats were administrated with PBS by caudal vein after 24h peritoneal injection of 6mg/mg cisplatin, short for g2. 1×106 MSCs were injected to rats after 24h peritoneal injection of cisplatin, short for g3. Kidneys from healthey rats were used as control, short for g1. Renal tissues were collected at day 5 after treatment. There were 44 micorRNAs changed with significance between g2 and g3, among which 36 microRNAs upregulated and 8 microRNAs downregulated. Overall design: Cisplatin induced microRNAs expression in kidneys were profiled after administrated with PBS or MSCs for 4 days. In g2 and g3,three independent experiments were performed, while two in g1.
Project description:Inflammation is a key component of pathological angiogenesis. Here we induce cornea neovascularisation using sutures placed into the cornea, and sutures are removed to induce a regression phase. We used whole transcriptome microarray to monitor gene expression profies of several genes Overall design: This was a time course study conprising two arms. In the suture IN arm, sutures were maintained in the cornea after the 0h time point, while suture OUT arm is where both sutures were removed from the cornea at the 0h timpoint. 0h timepoint is when sprouts were 3/4 the distance from the pre-existing limbal vessels towards the sutures. Microarrays were performed at 0h, 24h suture IN and 24h suture OUT. Non sutured eyes from separate animals were used as controls. At each time point except for 0h=3 rats, the rest of the timepoints had four rats each.
Project description:Hypertension and persistent activation of the renin-angiotensin system (RAS) are predisposing factors for development of acute kidney injury (AKI). Although bone marrow-derived stromal cells (BMSCs) have shown therapeutic promise in treatment of AKI, the impact of pathological RAS on BMSC functionality has remained unresolved. RAS and its local components in the bone marrow are involved in several key steps of cell maturation processes. This may also render BMSC population vulnerable to alterations even in the early phases of RAS pathology. We isolated TG-BMSCs from young, end organ disease-free rats with increased RAS activation (human angiotensinogen/renin double transgenic rats; dTGR) that eventually develop hypertension and die of end-organ damage and kidney failure at 8-weeks-of-age. Control cells were isolated from wild-type Sprague-Dawley rats (SD-BMSCs). Cell phenotype, mitochondrial reactive oxygen species (ROS) production and respiration were assessed, and gene expression profiling was carried out using microarrays. Cells’ therapeutic efficacy was evaluated in a rat model of acute ischemia-reperfusion-induced AKI. Serum urea and creatinine were measured at 24h and 48h. Acute tubular damage was scored and immunohistochemistry was used for evaluation for markers of inflammation (MCP-1, ED-1), and kidney injury (KIM-1, NGAL). TG-BMSCs showed distinct mitochondrial morphology, decreased cell respiration, and increased production of ROS. Gene expression profiling revealed a pronounced pro-inflammatory phenotype. In contrast to the therapeutic effect of SD-BMSCs, administration of TG-BMSCs in the AKI model resulted in exacerbation of kidney injury and high mortality. Our results demonstrate that early persistent RAS activation can dramatically compromise therapeutic potential of BMSCs by shift into a pro-inflammatory phenotype with mitochondrial dysfunction. A comparison of transcriptome of a bone marrow-derived stromal cells from a double-transgene rats compared to those from control rats
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:Animal experiments were performed with male Sprague-Dawley rats (Charles River Laboratories, Boston, MA) weighing 150 ? 200 grams. All experimental protocols used in this study were approved by the Subcommittee on Research Animal Care, Massachusetts General Hospital. Rats were individually housed in a temperature-controlled (25oC) and light-controlled room (12h light-dark cycle) and allowed to adjust to their new surroundings for at least 5 days prior to the experiment. Water and rat chow were provided ad libitum to the animals. On the day of the treatment, the animals were randomly divided into two groups, burned and sham-burned. The burn injury consisted of a full-skin-thickness scald burn of the dorsum, calculated to be ~ 20% of the rat?s total body surface area (TBSA), induced by immersing the designated area in boiling water for 10 s (45). Rats were resuscitated with an intra-peritoneal injection of sterile saline solution (1.5 mL/Kg body weight/% TBSA) immediately after burn. The mortality rate of this treatment was negligible. At each time point (1, 2, 4, and 7d), three animals belonging to each group were sacrificed, the liver and serum collected, and stored at ?80oC after being inflicted with 20% TBSA burn injury. Sham-burn rats (n=3) considered as the control were treated identically except that they were immersed into a 37oC water bath and immediately sacrificed to collect the livers.
Project description:characterization of fibrinogen expression in the kidney, excretion in the urine following kidney damage and evaluating the therapeutic potential of fibrinogen in acute kidney injury. Overall design: Total RNA was isolated of renal cortex and medulla from rats subjected to 20 min of bilateral ischemia followed by 6, 24 120, hr of reperfusion compared to sham rats.