Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0035078 (renal failure)
 31,970 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fibronectin (Fn), an acute phase glycoprotein synthesized by the liver, has an important immunomodulatory role. We have investigated the changes in plasma Fn in patients after renal transplantation in order to determine whether these changes predict graft injury or rejection episodes. Besides normal healthy controls, healthy pregnant controls, and a trauma control group, we used two groups of chronic renal failure patients as controls: group I, patients with end-stage renal failure (ESRF) on peritoneal dialysis; group II, patients with ESRF on hemodialysis. These were compared with two groups of renal transplant patients: group III, patients 3 months after successful renal transplantation; group IV, patients studied sequentially 10 days immediately posttransplantation. The renal transplant patients were treated with low-dose cyclosporine, azathioprine, and steroids. Citrated plasma samples were collected for Fn assay by a sandwich-type ELISA and for SDS-PAGE analysis and Western blotting. The mean plasma Fn levels were as follows: healthy controls 311.6 SEM, 13.5 micrograms/ml; healthy pregnant controls 357 SEM, 5.9 micrograms/ml; trauma controls 262.3 SEM 31.7, micrograms/ml; group I 169 SEM, 25.1 micrograms/ml; group II 199 SEM, 27.2 micrograms/ml; group III 272 SEM, 21.7 micrograms/ml; group IV 212 SEM, 27.4 micrograms/ml (day 3 postop). There was a significant difference in the plasma Fn levels on day 3 posttransplant between the patients with delayed and immediate renal function (P less than 0.03) (group IV). A significant decrease in plasma Fn levels occurred immediately after steroid therapy was stopped (P less than 0.03) in patients treated for acute rejection. Plasma Fn levels were significantly decreased in the presence of delayed graft function but did not predict rejection.
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PMID:Plasma fibronectin levels during acute rejection and acute tubular necrosis in renal transplant patients. 141 24

Polycystic kidney disease is an inherited disorder of parenchymal structure that leads to renal failure. Cysts begin as focal dilations in proximal tubules and collecting ducts, giving rise to cyst walls lined by a phenotypically disturbed epithelium that expresses dysfunctional transport and matrix proteins. We used an mRNA search protocol to probe efficiently for tissue-specific disturbances that might underlie the formation of cysts. This search assessed the relative abundance of transcripts encoding a variety of growth factors (transforming growth factor-beta 1, interleukin-6, tumor necrosis factor, and endothelin-1), structural proteins (collagen IV, nidogen, fibronectin, and laminins A and B1), and cell adhesion molecules (CAMs; E-cadherin, N-CAM, laminin receptor, and fibronectin receptor) in the cystic kidneys of cpk/cpk mice and uncovered a previously unrecognized early reduction in mRNA encoding N-CAM (54%) and E-cadherin (56%) (n = 5; P less than 0.001). Levels of transcripts for growth factors, structural proteins, and for fibronectin and laminin receptors in normal and cystic kidneys were generally similar. The reduction in transcripts for N-CAM and E-cadherin in kidneys from cystic mice was not observed in autologous liver. The immunofluorescent staining of cystic kidneys confirmed that the decrease in N-CAM and E-cadherin was generally confined to regions abundant in developing cystic epithelium. The presence of both N-CAM and E-cadherin appears to guide the sequential differentiation and polarization of normal renal epithelium, and their attenuated expression in the kidney of cpk/cpk mice may be a material factor contributing to the pathogenesis of cyst formation.
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PMID:Attenuated expression of epithelial cell adhesion molecules in murine polycystic kidney disease. 156 81

The glomerular and tubular basement membranes are the principal barriers to filtration and re-absorption of water and molecules in the nephron. They are composed primarily of type IV collagen, laminin, fibronectin, sulphated proteoglycans and collagen type I. Three common inherited diseases are associated with abnormalities of basement membrane proteins: Alport's syndrome, thin basement membrane disease (TBMD) and adult polycystic kidney disease. In this review we describe the application of molecular biological techniques to the study of these conditions. Classic Alport's syndrome is an X-linked disorder with a lamellated glomerular basement membrane (GBM) which typically results in renal failure in males. Studies with sera from patients with Goodpasture's syndrome, or monoclonal antibodies specific for the Goodpasture antigen, show that the Goodpasture antigen is absent or masked in the kidneys of individuals with Alport's syndrome. There is some evidence to suggest that the Goodpasture antigen is best represented by the non-collagenous domain of the alpha 3 chain of type IV collagen, but that other non-collagenous regions may also contribute to the antigen. It is through these non-collagenous regions that the type IV collagen chains form the typical network, and the abnormality in Alport's syndrome interferes with this network formation. However, we have recently demonstrated that the gene for the non-collagenous domain of the alpha 3 collagen chain is present in individuals with Alport's syndrome. Furthermore, other groups have shown a defect in a novel type IV collagen chain, the alpha 5 chain, in 3 unrelated cases of Alport's syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hereditary abnormalities of renal basement membranes. 168 82

Plasma and urine concentrations of factor XIII and its circulating substrates (fibronectin, fibrinogen, and alpha 2-antiplasmin) were measured in a group of 36 patients with nephrotic syndrome. The results were compared with those obtained in a group of 32 normal volunteers (control group) and 12 patients with end-stage renal disease (ESRD). A mild but significant reduction in plasma level and an abnormal urinary excretion of alpha 2-antiplasmin was found in the nephrotic group. Plasma concentrations of factor XIII, fibronectin, and fibrinogen were significantly elevated in patients with nephrosis. In contrast, patients with ESRD showed no significant difference in the plasma concentrations of either factor XIII, fibronectin, or alpha 2-antiplasmin and only a modest elevation of fibrinogen when compared with normal controls. No significant correlation was found between serum creatinine concentration and plasma levels of factor XIII and its circulating substrates in the nephrotic group. No measurable quantities of factor XIII and only small quantities of fibronectin were found in the urine of patients with nephrosis. Elevation of plasma factor XIII, fibronectin, and fibrinogen concentrations in the nephrotic group is considered to be the result of a combination of increased synthesis and possibly contracted intravascular distribution of these macromolecular proteins in the face of their negligible urinary losses. The presence of the observed abnormalities in the nephrotic group and their absence in the non-nephrotic ESRD group tends to exclude renal failure as a cause of these abnormalities. Although the clinical significance of these abnormalities is uncertain, they can potentially contribute to the thrombophilic diathesis and platelet hyperaggregability in nephrotic syndrome.
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PMID:Factor XIII and its substrates, fibronectin, fibrinogen, and alpha 2-antiplasmin, in plasma and urine of patients with nephrosis. 199 57

Crescents are a severe and stereotyped glomerular response to injury that occur in several forms of glomerulonephritis that progress to renal failure. The key pathogenetic step that leads to glomerular scarring in unknown, but fibronectin (FN), the clotting system, macrophages, and proliferating parietal epithelial cells are known to participate. This study was designed to determine whether FN is synthesized locally, and in what molecular isoform, and whether cytokines known to promote FN synthesis are present in the crescent. Rats immunized with bovine glomerular basement membrane develop cellular crescents by 14 days and fibrous crescents and glomerulosclerosis by 35 days. In situ hybridization was performed with oligonucleotides specific for sequences common to all FN isoforms (total FN) or sequences specific for the alternatively spliced segments (EIIIA, EIIIB, and V). Throughout the time period (14, 21, and 35 days) all crescents and glomerular tufts contained cells with strong ISH signals for total and V+ mRNA, with the strongest signals present in large cellular crescents at day 21. In contrast, EIIIA+ and EIIIB+ mRNAs showed maximal abundance within sclerosing crescents at 35 days. Protein deposition of EIIIA+, EIIIB+, and V+ FN isoforms was confirmed by immunofluorescence with segment-specific FN antibodies. Transforming growth factor-beta and interleukin-1 beta, both known to promote FN synthesis, were found in cellular crescents (days 14 and 21) and were still present, but greatly diminished, in the sclerotic phase (day 35). In summary, EIIIA-, EIIIB-, and V+ FN mRNA plasma isoforms predominate in cellular crescents, whereas in the fibrosing stage, mainly the oncofetal EIIIA+, EIIIB+, and V+ isoforms are synthesized and accumulate.
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PMID:Embryonic fibronectin isoforms are synthesized in crescents in experimental autoimmune glomerulonephritis. 757 72

We have studied the sequential morphological changes that took place in the kidneys of 8 rats with nephrotoxic serum nephritis (NTN). Rats underwent kidney biopsies at different time intervals (days 7, 15, 30, 90 and 120). The tissues were processed for light microscopy as well as immunohistochemistry for inflammatory cellular infiltrate as well as for the components of the extracellular matrix (ECM) and myofibroblasts (cells expressing alpha-smooth muscle actin, alpha-SMA). Nephrotic rats developed severe proteinuria, impaired renal function as well as progressive renal scarring. However, the natural history of NTN was heterogeneous with some rats recovering (n = 5) and other progressing to end-stage renal failure (n = 3). The heterogeneous nature of the glomerulonephritis has established that those with a good outcome had a stabilisation, with some resolution, of the deposited ECM and of the scarring process. By contrast, rats with a poor outcome had a progressive increase in glomerular as well as interstitial ECM. Cells expressing alpha-SMA (myofibroblasts) were detected in the glomeruli as well as in the interstitium of nephritic rats. Changes in the expression of cells expressing alpha-SMA paralleled those of the components of the ECM in particular fibronectin. alpha-SMA immunostain was the best predictor of progression. Early glomerular alpha-SMA immunostain (days 7 and 30) was a strong predictor of the subsequent development of glomerulosclerosis and renal dysfunction. The predictive value of interstitial alpha-SMA immunostain on days 7 for subsequent tubulo-interstitial scarring and renal insufficiency was also strong and exceeded that of other histological or immunohistochemical parameters of scarring. This study establishes the natural history of experimental renal scarring and identifies a renal cell type, the myofibroblast, as a useful marker of progression. It also suggests a role for myofibroblasts in the progression of glomerulosclerosis and tubulo-interstitial fibrosis.
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PMID:Myofibroblasts and the progression of experimental glomerulonephritis. 758 53

Familial nephronophthisis is one of the inherited human cystic kidney diseases and is characterized by progressive renal failure. We have investigated abnormalities of cell-matrix interactions using immunocytochemistry and electron microscopy in three renal biopsies from two patients with familial nephronophthisis and compared our findings to those seen in thirty other renal biopsies. We found expression of the alpha 5 integrin fibronectin receptor in all three samples of nephronophthisis but in no other renal diseases. There was also enhanced expression of the alpha 2 integrin in nephronophthisis but this appeared to be a common response to tubular injury. Electron microscopy showed thickening of the tubular basement membrane and a loss of organization of the basal pole of tubular epithelium. We conclude that altered cell-substratum adhesion contributes to the pathogenesis of nephronophthisis.
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PMID:Abnormal integrin receptor expression in two cases of familial nephronophthisis. 760 23

Diabetes is now the most common cause of progressive kidney failure leading to dialysis or transplantation. The central pathological feature of diabetic nephropathy is accumulation of extracellular matrix within the glomeruli. The factors in the diabetic milieu responsible for extracellular matrix accumulation are not understood. Here we report that in glomeruli of rats made diabetic there is a slow, progressive increase in the expression of transforming growth factor beta (TGF-beta) mRNA and TGF-beta protein. A key action of TGF-beta is induction of extracellular matrix production, and specific matrix proteins known to be induced by TGF-beta were increased in diabetic rat glomeruli. These proteins include an alternatively spliced form of fibronectin, tenascin, and the proteoglycan biglycan. TGF-beta has not previously been implicated in the matrix accumulation that occurs in the diabetic kidney. Glomeruli from humans with diabetic nephropathy also showed a striking increase in immunoreactive TGF-beta protein and deposition of the special form of fibronectin, whereas glomeruli from normal subjects or from individuals with other glomerular diseases (where extracellular matrix accumulation is not a feature) were negative or barely positive. These results implicate TGF-beta in the pathogenesis of diabetic nephropathy.
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PMID:Expression of transforming growth factor beta is elevated in human and experimental diabetic nephropathy. 768 Apr 80

Mesangial cell (MC) proliferation and extracellular matrix expansion are involved in the pathogenesis of glomerulosclerosis and renal failure. In vitro, PDGF and basic fibroblast growth factor (bFGF) regulate MC proliferation and/or matrix production. To elucidate the role of PDGF and bFGF in vivo, equimolar concentrations of recombinant PDGF-BB or bFGF or vehicle were infused intravenously into rats over a 7-d period. Rats were either nonmanipulated ("normals") or had received a subnephritogenic dose of anti-MC antibody ("anti-Thy 1.1 rats") before the infusion period. Glomerular cell proliferation (anti-proliferating cell nuclear antigen immunostaining) on days 2, 4, and 7 was unchanged in vehicle-infused normals or anti-Thy 1.1 rats. PDGF infusion increased glomerular cell proliferation 32-fold in anti-Thy 1.1 rats and an 11-fold in normals on day 2. bFGF increased glomerular cell proliferation fourfold in anti-Thy 1.1 rats but was ineffective in normals. Induction of cell proliferation in all kidneys was limited to the glomerulus. The majority of proliferating cells were identified as MC by double immunolabeling. No significant proteinuria, glomerular leukocyte, or platelet influx developed in any group. Glomerular matrix expansion with increased deposition of type IV collagen, laminin, and fibronectin, as well as upregulated laminin and collagen IV mRNA expression was confined to PDGF-infused anti-Thy 1.1 rats. These results show that PDGF and, to a lesser degree, bFGF are selective MC mitogens in vivo and that previous subclinical injury can enhance this MC response. The data thereby support a role of these cytokines in the pathogenesis of glomerulosclerosis.
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PMID:Infusion of platelet-derived growth factor or basic fibroblast growth factor induces selective glomerular mesangial cell proliferation and matrix accumulation in rats. 790 49

Kaspareit-Rittinghausen described a rodent model of inherited polycystic kidney disease (PKD), the Han:SPRD rat [1, 2], in which heterozygotes develop renal cysts and renal failure (in males) over several months, whereas homozygous animals develop rapidly progressive renal enlargement that leads to death in a few weeks. In this study, we examined selected elements of the pathogenesis of this disease in heterozygotes and homozygotes from birth to advanced disease. Heterozygous male rats developed slowly progressive renal cystic disease with interstitial fibrosis and azotemia seen by six months of age. Female heterozygotes developed slowly progressive renal cystic disease, but did not develop interstitial fibrosis or azotemia. Epithelial cells lining cyst cavities showed various degrees of morphologic immaturity. Cyst walls also developed basement membrane thickening, especially in areas of cellular immaturity, suggesting an interrelationship between this basement membrane thickening and cellular dedifferentiation. Thickened basement membranes were associated with increased immunoreactivity for type IV collagen, laminin, and fibronectin. Homozygous rats developed massive renal enlargement, marked azotemia, and died near three weeks of age. Renal c-myc proto-oncogene expression was elevated in homozygous cystic infants and in adult heterozygotes. In situ hybridization showed high levels of c-myc mRNA in cyst epithelia, suggesting abnormal regulation of cellular proliferation in the cells lining cysts, as seen in other models of PKD. The Han:SPRD rat is the only well-documented animal model of inherited PKD with an autosomal-dominant inheritance pattern and appears to have several features which resemble human ADPKD.
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PMID:Autosomal-dominant polycystic kidney disease in the rat. 845 52


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