Project description:Nature exploits cage-like proteins for a variety of biological purposes from molecular packaging and cargo delivery to catalysis. These cage-like proteins are of immense importance in nanomedicine due to their propensity to self-assemble from simple identical building blocks to highly-ordered architecture and the design flexibility afforded by protein engineering. However, delivery of protein nanocages to the renal tubules remains a major challenge because of the glomerular filtration barrier, which effectively excludes conventional size nanocages. Here we show that DNA-binding Protein from Starved cells (Dps)—the extremely small archaeal antioxidant nanocage—is able to cross the glomerular filtration barrier and is endocytosed by the renal proximal tubules. Using a model of endotoxemia, we present an example of the way in which proximal tubule-selective Dps nanocage can limit the degree of endotoxin-induced kidney injury. This was accomplished by amplifying the endogenous antioxidant property of Dps with addition of a dinuclear manganese cluster. Dps is the first-in-class, protein cage nanoparticle that can be targeted to renal proximal tubules through glomerular filtration. In addition to its therapeutic potential, chemical and genetic engineering of Dps will offer a novel nanoplatform to advance our understanding of the physiology and pathophysiology of glomerular filtration and tubular endocytosis.
Project description:Our objective is to monitor glomerular filtration rate (GFR)during the perioperative phase of patients undergoing robotic surgery for rectum or large bowel cancers. We will use both a single injection and a continuous infusion of iohexol to measure kidney function for 72 hours after surgery.
Project description:Dent disease has multiple defects attributed to proximal tubule malfunction including low molecular weight proteinuria, aminoaciduria, phosphaturia and glycosuria. In order to understand the changes in kidney function of the Clc5 transporter gene knockout mouse model of Dent disease, we examined gene expression profiles from proximal tubules of mouse kidneys. Overall 720 genes are expressed differentially in the proximal tubules of the Dent Clcn5 knockout mouse model compared to those of control wild type mice. The fingerprint of these gene changes may help us to understand the phenotype of Dent disease. Experiment Overall Design: Renal proximal tubules were dissected from wild type and Clcn5 knockout mice. Mice were anesthetized with halothane, the abdominal aorta of each animal was accessed and the left kidney was perfused with an ice-cold salt. Proximal tubule dissection was performed in an ice-cold salt solution. After dissection of approximately 80-100 segments of 2 mm in length per kidney, the RNA for 3-4 mice was combined to have enough RNA per chip. Experiment Overall Design: 3 microarrays each of wild type and knockout mouse proximal tubule were processed
Project description:Multipotent progenitor cells (MPs) have been observed in human kidneys and particularly in Bowman's capsule and proximal tubules. The kidney owns the ability to repair local damage and renal MPs may play a role in the regenerative processes. Microarray technology was applied to identify differentially expressed genes among resident MPs isolated from glomeruli and tubules of normal renal tissue, renal proximal tubular epithelial cells (RPTECs) and mesenchymal stem cells (MSCs). The results of our analysis represent a starting point for further functional studies. Experiment Overall Design: This study includes three renal tissue samples which were processed to obtain 3 glomerular progenitor populations and 3 tubular ones. Three subcoltures of MSCs and RPTECs were included as well. The differences in gene expression patterns of the 4 cell types were found out.
Project description:Dent disease has multiple defects attributed to proximal tubule malfunction including low molecular weight proteinuria, aminoaciduria, phosphaturia and glycosuria. In order to understand the changes in kidney function of the Clc5 transporter gene knockout mouse model of Dent disease, we examined gene expression profiles from proximal tubules of mouse kidneys. Overall 720 genes are expressed differentially in the proximal tubules of the Dent Clcn5 knockout mouse model compared to those of control wild type mice. The fingerprint of these gene changes may help us to understand the phenotype of Dent disease. Keywords: gene knockout, mouse, Clcn5, Dent's disease
Project description:dB/dB mice develop different kidney pathologies resulting from high body weight. We seek to better understand the mechanisms of this kidney damage in proximal tubules. We isolated RNA from proximal tubules of different groups of mice, and we seek to understand how the anti-oxidant enzyme catalase may regulate kidney damage in this model.
Project description:Circadian variability in kidney function has long been recognized but is often ignored as a potential confounding variable in in vivo physiological experiments. To provide a guide for physiological studies on the kidney proximal tubule, we have now created a data resource consisting of expression levels for all measurable mRNA transcripts in microdissected proximal tubule segments from mice as a function of the time of day. This approach employs small-sample RNA-sequencing (RNA-seq) applied to microdissected renal proximal tubules including both S1 proximal convoluted tubules (PCTs) and S2 proximal straight tubules (PSTs). The data were analyzed using JTK-Cycle to detect periodicity. The data are provided as a user-friendly web page at https://esbl.nhlbi.nih.gov/Databases/Circadian-Prox/. In PCTs, 234 transcripts were found to vary in a circadian manner (3.7 % of total quantified). In PSTs, 334 transcripts were found to vary in a circadian manner (5.3 % of total quantified). Transcripts previously known to be associated with corticosteroid action and transcripts associated with increased flow were found to be overrepresented among circadian transcripts peaking during the “dark” portion of the day (Zeitgeber 14-22), corresponding to the peak levels of corticosterone and glomerular filtration rate in mice.
Project description:To clarify the effects of cisplatin (cis-diamminedichloroplatinum II, CDDP) on the gene expression profiles in renal proximal tubules, microarray analyses were carried out using total RNA samples isolated from microdissected proximal tubules and whole kidneys. The molecular events underlying acute kidney injury (AKI) in the proximal tubules of rats with cisplatin-induced nephrotoxicity were successfully clarified with 17,000 transcripts. Renal proximal tubules were isolated under microscopy, and transcriptome data were collected with Rat Genome Survey Microarray® (Applied Biosystems)
Project description:To clarify the effects of cisplatin (cis-diamminedichloroplatinum II, CDDP) on the gene expression profiles in renal proximal tubules, microarray analyses were carried out using total RNA samples isolated from microdissected proximal tubules and whole kidneys. The molecular events underlying acute kidney injury (AKI) in the proximal tubules of rats with cisplatin-induced nephrotoxicity were successfully clarified with 17,000 transcripts.