Project description:8 week-old male C57BL6J mice were given Gram-negative endotoxin (LPS O111:B4, 10 mg/kg) intraperitoneally at time 0. 18 hrs thereafter, they were administered 10 ml/kg 0.9% saline. Mice were sacrificed at 0, 18, or 42 hrs after LPS challenge. Kidneys were immediately collected into TRIzol for RNA preparation. Renal function was measured on blood collected at the time of tissue harvest At t=0hr, mice had normal baseline renal function. At t=18hr, mice exhibited early renal injury, At t=42hr, mice had either recovered normal renal function or had persistent renal injury. We collected kidneys from 3 mice per time point. For the 42 hr time point, we collected kidneys from 3 mice with recovered renal function and kidneys from 3 mice with persistent renal injury. Mouse kidneys selected at successive stages of renal injury and recovery following systemic LPS challenge and volume resuscitation following LPS challenge.
Project description:We recently developed a new model of renal agenesis [i.e., the heterogeneous stock derived model of unilateral renal agenesis, (HSRA)]. The HSRA model consistently exhibits unilateral renal agenesis ranging from 50-75% in each generation and is characterized by low nephron number, early kidney hypertrophy, and an inherent susceptibility to develop significant kidney injury and decline in renal function with age. Whole transcriptome analysis was evaluated at month 1 to identify early changes in genes/networks that may be involved in increased susceptibility of HSRA-S to develop kidney injury in the long-term. An n=4 per group (independent samples) were evaluated for HSRA-S (congenital solitary kidney) and HSRA-C (two-kidney). HSRA-C (two-kidney) samples were set as the control.
Project description:We recently developed a new model of renal agenesis [i.e., the heterogeneous stock derived model of unilateral renal agenesis, (HSRA)]. The HSRA model consistently exhibits unilateral renal agenesis ranging from 50-75% in each generation and is characterized by low nephron number, early kidney hypertrophy, and an inherent susceptibility to develop significant kidney injury and decline in renal function with age. Whole transcriptome analysis was evaluated at month 1 to identify early changes in genes/networks that may be involved in increased susceptibility of HSRA-S to develop kidney injury in the long-term.
Project description:Angiotensin II (Ang II) mediated signaling plays a key role in the development of hypertension associated target organ damages. However, the gene expression changes regulated by Ang II in the early stage of acute cerebral, cardiac, renal, vascular injury remain unclear. we investigated Ang II–mediated gene expression alteration associated with the development of early cerebral, cardiac, renal, vascular injury by microarray assay in a mouse model.
Project description:Angiotensin II (Ang II) mediated signaling plays a key role in the development of hypertension associated target organ damages. However, the gene expression changes regulated by Ang II in the early stage of acute cerebral, cardiac, renal, vascular injury remain unclear. we investigated Ang II–mediated gene expression alteration associated with the development of early cerebral, cardiac, renal, vascular injury by microarray assay in a mouse model.
Project description:Background: The inflammatory response to acute kidney injury (AKI) likely dictates future renal health. Lymphatic vessels are responsible for maintaining tissue homeostasis through transport and immunomodulatory roles. Due to the relative sparsity of lymphatic endothelial cells (LECs) in the kidney, past sequencing efforts have not characterized these cells and their response to AKI. Methods: Here we characterized murine renal LEC subpopulations by single-cell RNA sequencing and investigated their changes in cisplatin AKI 72 hours post injury. Data was processed using the Seurat package. We validated our findings by qPCR in LECs isolated from both cisplatin-injured and ischemia reperfusion injury, by immunofluorescence, and confirmation in in vitro human LECs. Results: We have identified renal LECs and their lymphatic vascular roles that have yet to be characterized in previous studies. We report unique gene changes mapped across control and cisplatin injured conditions. Following AKI, renal LECs alter genes involved in endothelial cell apoptosis and vasculogenic processes as well as immunoregulatory signaling and metabolism. Differences between injury models were also identified with renal LECs further demonstrating changed gene expression between cisplatin and ischemia reperfusion injury models, indicating the renal LEC response is both specific to where they lie in the lymphatic vasculature and the renal injury type. Conclusions: In this study, we uncover lymphatic vessel structural features of captured populations and injury-induced genetic changes. We further determine LEC gene expression is altered between injury models. How LECs respond to AKI may therefore be key in regulating future kidney disease progression.
Project description:Congenital obstructive nephropathy is a common cause of chronic kidney disease and a leading indication for renal transplant in children. The cellular and molecular responses of the kidney to congenital obstruction are incompletely characterized. In this study, we evaluated global transcription in kidneys with graded hydronephrosis in the megabladder (mgb-/-) mouse to better understand the pathophysiology of congenital obstructive nephropathy. Three primary pathways associated with kidney remodeling/repair were induced in mgb-/- kidneys independent of the degree of hydronephrosis. These pathways included retinoid signaling, steroid hormone metabolism, and renal response to injury. Urothelial proliferation and the expression of genes with roles in the integrity and maintenance of the renal urothelium were selectively increased in mgb-/- kidneys. Ngal/Lcn2, a marker of acute kidney injury, was elevated in 36% of kidneys with higher grades of hydronephrosis. Evaluation of Ngalhigh versus Ngallow kidneys identified the expression of several novel candidate markers of renal injury. This study indicates that the development of progressive hydronephrosis in mgb-/- mice results in renal adaptation that includes significant changes in the morphology and potential functionality of the renal urothelium. These observations will permit the development of novel biomarkers and therapeutic approaches to progressive renal injury in the context of congenital obstruction. Gene expression was measured in control, mild, moderate and severely hydronephrotic megabladder mouse kidneys. A total of 6 control kidneys were compared to 18 mutant kidneys from age-matched male animals.
Project description:8 week-old male C57BL6J mice were given Gram-negative endotoxin (LPS O111:B4, 10 mg/kg) intraperitoneally at time 0. 18 hrs thereafter, they were administered 10 ml/kg 0.9% saline. Mice were sacrificed at 0, 18, or 42 hrs after LPS challenge. Kidneys were immediately collected into TRIzol for RNA preparation. Renal function was measured on blood collected at the time of tissue harvest At t=0hr, mice had normal baseline renal function. At t=18hr, mice exhibited early renal injury, At t=42hr, mice had either recovered normal renal function or had persistent renal injury. We collected kidneys from 3 mice per time point. For the 42 hr time point, we collected kidneys from 3 mice with recovered renal function and kidneys from 3 mice with persistent renal injury.
Project description:Tissue inhibitors of metalloproteinases (TIMP) are endogenous inhibitors of matrix metalloproteinases (MMP). While TIMP2 and TIMP3 inhibit MMPs, TIMP3 also inhibits activation of pro-MMP2 whereas TIMP2 promotes it. Here we assessed the differential role of TIMP2 and TIMP3 in renal injury using the unilateral ureteral obstruction model. Gene microarray assay showed that post-obstruction, the lack of TIMP3 had a greater impact on gene expression of intermediate, late injury- and repair-induced transcripts, kidney selective transcripts and solute carriers. Renal injury in TIMP3-/-, but not in TIMP2-/- mice increased expression of collagen type I/III, connective tissue growth factor, transforming growth factor-β and the downstream Smad2/3 pathway. Interestingly, ureteral obstruction markedly increased MMP2 activation in the kidneys of TIMP3-/- mice which was completely blocked in the kidneys of TIMP2-/- mice. These changes are consistent with enhanced renal tubulointerstitial fibrosis in TIMP3-/- and its reduction in TIMP2-/- mice. The activity of tumor necrosis factor-α converting enzyme, caspase-3 and mitogen activated kinases were elevated in the kidneys of TIMP3-/- but not TIMP2-/- mice, suggesting enhanced activation of apoptotic and pathological signaling pathways only in the obstructed kidney of TIMP3-/- mice. Thus, TIMP2 and TIMP3 play differential and contrasting roles in renal injury, TIMP3 protects from damage whereas TIMP2 promotes injury through MMP2 activation. Kidneys from the wild type (WT), TIMP2-/- and TIMP3-/- mice undergoing sham or unilateral ureteral obstruction (UUO) procedures