Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Proteinuria and progressive glomerulosclerosis are commonly associated with nephron loss. We studied the pathogenesis of these lesions by examining the role of changes in specific glomerular capillary wall permeability properties in uninephrectomized rats. The development of altered capillary permselectivity to macromolecules and loss of glomerular basement membrane anionic charge were measured by the dextran fractional clearance and ferritin tracer probe methods, respectively. In addition, the protective effect of dietary protein restriction and an angiotensin I-converting enzyme inhibitor (captopril) were studied in eight groups of male Sprague-Dawley rats. Four groups of rats underwent sham-nephrectomy or left nephrectomy and were fed an 8.5% protein diet (sham-nephrectomy and low protein, nephrectomy and low protein) or a 30% protein diet, respectively (sham-nephrectomy and high protein, nephrectomy a high protein). Four other groups of rats underwent sham-nephrectomy or left nephrectomy and were treated with captopril (50 mg/kg/day) while receiving a 8.5% protein diet (sham-nephrectomy, low protein and captopril, nephrectomy, low protein and captopril) or a 30% protein diet, respectively (sham-nephrectomy, high protein and captopril, nephrectomy, high protein and captopril). Rats were nephrectomized at 21 days of age and were functionally tested and sacrificed at 7 months of age. The nephrectomy and high protein rats had significantly greater proteinuria and higher fractional clearance of neutral dextrans in the 30 to 42 A range compared with that of sham-nephrectomy and high protein, nephrectomy and low protein, and nephrectomy, high protein and captopril rats. The nephrectomy and high protein rats also had a significantly lower labeling of the glomerular basement membrane with cationic ferritin tracer molecules compared with the nephrectomy and low protein and nephrectomy, high protein and captopril rats. Of the eight treatment groups, the nephrectomy and high protein rats had the most severe glomerular lesions. In general, nephrectomized rats fed low dietary protein and nephrectomized rats treated with captopril had significantly less proteinuria, glomerular lesions, and milder changes in the glomerular capillary wall porosity and glomerular basement membrane anionic charge.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Effects of dietary protein and captopril on glomerular permselectivity in rats with unilateral nephrectomy. 245

Recent studies have suggested a role for thromboxane in the progression of renal disease. The current study evaluated the role of this arachidonic acid metabolite in a model of renal disease which bears many biologic similarities to that in the kidneys of patients with chronic progressive renal failure. The model is that induced by ferritin-anti-ferritin immune complex nephritis in Dahl-salt sensitive rats rendered hypertensive by a high salt intake. Rats with this model of renal disease were chronically given a thromboxane synthetase antagonist OKY-046 or a placebo treatment from 16 to 29 weeks of age. Sequential observations of serum creatinine and 24-hour urinary protein excretion showed an ameliorating effect of OKY-046 on these renal parameters. Histologic examination of the kidneys also showed significantly less glomerular sclerosis in OKY-046 treated animals. The efficacy of OKY-046 was monitored by measurements of serum TXB2 levels and of glomerular production of TXB2 (and other prostaglandins); amounts of TXB2 were significantly reduced in the OKY-046 group. It is concluded that blockade of thromboxane generation has been successful in ameliorating the functional and structural lesions in this model of renal disease, providing further support to the thesis that thromboxane is an important mediator in events leading to eventual chronic renal failure and sclerosis.
 ...
PMID:A thromboxane synthetase antagonist ameliorates progressive renal disease of Dahl-S rats. 296 73

Male BALB/c mice given daily intraperitoneal injections of 4 mg of horse-spleen apoferritin develop, in the majority of cases, a proliferative and necrotizing glomerulonephritis with leukocytic infiltration and extensive intraglomerular thrombosis within 10 to 14 days, as previously reported. We now show that if injection of the antigen is discontinued, surviving animals develop extensive glomerulosclerosis (GS). Ten of 13 mice treated as indicated above and sacrificed 4 months after the last horse-spleen apoferritin injection developed segmental GS involving over 40% of their glomeruli. Tubulointerstitial damage of proportionate severity also developed. Ultrastructurally, pronounced mesangial expansion due to matrix deposition obliterated the glomerular architecture. We offer this as a reproducible model of immune complex-mediated GS particularly suited to the study of cellular interactions involved in the pathogenesis of GS.
 ...
PMID:Immune complex acute necrotizing glomerulonephritis with progression to diffuse glomerulosclerosis. A murine model. 297

The relationship between hypertension, ferritin-antiferritin mesangial immune injury (FIC), and progressive glomerular damage was studied in hypertensive (8% NaCl chow) Dahl salt-sensitive rats (DS) and in spontaneously hypertensive rats (SHR). The glomeruli of SHR are protected from the increased perfusion pressure that accompanies systemic hypertension by preglomerular vasoconstriction, while the glomeruli of hypertensive DS are not. Blood pressure, serum creatinine levels, urinary protein excretion, and glomerular injury (assessed by semiquantitative morphometric analysis) were determined in 20-week-old SHR and DS with FIC. In addition, half of a group of 20-week-old SHR with FIC were uninephrectomized and progression of glomerular injury was assessed 12 weeks later. Control rats for each of the groups did not receive FIC. Our studies showed that more extensive mesangial expansion and glomerulosclerosis developed in hypertensive DS with FIC than in rats without FIC. Glomerular injury in DS with FIC affected cortical and deep glomeruli. Similarly, hypertensive SHR with FIC had minimal damage in cortical glomeruli. In deep glomeruli of SHR, mesangial expansion was similar to that of DS, but glomerulosclerosis was absent. In SHR, a 50% reduction in renal mass, a maneuver known to decrease preglomerular vasoconstriction, resulted in mesangial expansion similar to that in DS in cortical glomeruli while deep glomeruli developed mesangial expansion as well as glomerulosclerosis. Our results suggest that when hypertension and mesangial immune injury coexist with renal vasodilatation (as occurs in DS with 2 kidneys and in SHR after uninephrectomy), they act synergistically to induce progressive glomerular damage. Similar mechanisms may be operative in hypertensive humans with glomerulonephritis and may condition the rate of progression to renal insufficiency.
 ...
PMID:Role of hypertension in progressive glomerular immune injury. 315 4

Hypertension frequently accompanies chronic glomerulonephritis. Mesangial injury and glomerulosclerosis are common in glomerulonephritis and are often harbingers of progressive glomerular destruction. Thus, in a model of mesangial immune injury we studied the relationship between hypertension, mesangial injury, and glomerulosclerosis. We induced mesangial ferritin-antiferritin immune complex disease (FIC) in Dahl salt-sensitive (S) and salt-resistant (R) rats. S and R rats with FIC were fed chow containing 0.3% NaCl until 14 weeks of age and then switched to 8.0% NaCl chow until 28 weeks of age. Groups of control S and R rats (no FIC) were either fed 0.3% NaCl for 28 weeks or switched to 8.0% NaCl chow at 14 weeks of age. Blood pressure, serum creatinine, urinary protein, and glomerular injury (assessed by semiquantitative morphometric analysis) were determined at 14 and 28 weeks of age. R rats with or without FIC did not develop hypertension; mesangial injury was minimal. At 14 weeks of age, only S FIC rats developed hypertension, proteinuria, significant mesangial expansion and early glomerulosclerosis. At 28 weeks of age, proteinuria, mesangial expansion, and glomerulosclerosis were significantly more severe in hypertensive S rats with FIC than in those without FIC. These studies show that despite a normal salt intake, mesangial injury hastened the onset of hypertension, but only in rats genetically predisposed to hypertension (S FIC at 14 weeks). High dietary salt further aggravated hypertension, which, in turn, magnified both mesangial injury and glomerulosclerosis. Clinically, the different rates of progression of human glomerulonephritis associated with hypertension may be in part dependent on similar mechanisms.
 ...
PMID:Mesangial immune injury, hypertension, and progressive glomerular damage in Dahl rats. 623 58

Since increased mesangial accumulation of matrix has been considered to be an important event in the development of focal glomerulosclerosis, we investigated whether morphine, an active metabolite of heroin, can modulate mesangial accumulation of immune complexes. Control or morphine-dependent rats were administered intraperitoneal ferritin (8 mg/100 g body weight) daily for 6 weeks. Body weight, blood pressure, serum creatinine, 24-hour urinary protein and creatinine excretion rates were measured at 3-week intervals. Rats were sacrificed at the end of 6 weeks and kidney tissue was studied by light, immunofluorescence and electron microscopy. Serum creatinine levels and urinary protein excretion rates were not different between control and morphine-dependent rats. All morphine-dependent rats developed hematuria, whereas only 1 control rat developed hematuria. Light microscopy revealed no proliferation of mesangial cells and only a minimal increase in the mesangial matrix. Electron-microscopic studies showed deposition of immune complexes in the mesangial region. Mesangial cells showed aggregation of ferritin in lysosomes. Immunofluorescence studies revealed the presence of IgG staining predominantly in the mesangial region. The majority (60%) of morphine-dependent rats showed a diffuse mesangial deposition of IgG when compared to control rats (83%) who showed only focal deposition. These results indicate that morphine enhances deposition of immune complexes in the mesangium. Morphine-induced matrix but may also change its quality. This may play a pathogenic role in the development of glomerular lesions in patients who abuse opiates.
 ...
PMID:Morphine enhances deposition of ferritin-antiferritin complexes in the glomerular mesangium. 756 9

Adriamycin, a commonly used antineoplastic antibiotic, induces glomerular lesions in rats, resulting in persistent proteinuria and glomerulosclerosis. We studied the effects of dietary protein and of an angiotensin I converting enzyme inhibitor on the progression of this nephropathy and the evolution of the histological lesions, as well as mesangial macromolecule flow. Adriamycin nephropathy was induced by injecting a single iv dose of adriamycin (3 mg/kg body weight) into the tail vein of male Wistar rats (weight, 180-200 g). In Experiment I animals with adriamycin-induced nephropathy were fed diets containing 6% (Low-Protein Diet Group = LPDG), 20% (Normal-Protein Diet Group = NPDG) and 40% (High-Protein Diet Group = HPDG) protein and were observed for 30 weeks. In Experiment II the rats with adriamycin nephropathy were divided into 2 groups: ADR, that received adriamycin alone, and ADR-ENA, that received adriamycin plus enalapril, an angiotensin I converting enzyme inhibitor. The animals were sacrificed after a 24-week observation period. Six hours before sacrifice the animals were injected with 131I-ferritin and the amount of 131I-ferritin in the glomeruli was measured. In Experiment III, renal histology was performed 4, 8 and 16 weeks after adriamycin injection. At the end of Experiment I the tubulointerstitial lesion index was 2 for LPDG, 8 for NPDG, and 7.5 for HPDG (P < 0.05); the frequency of glomerulosclerosis was 19 +/- 6.1% in LPDG, 42.6 +/- 6% in NPDG, and 54 +/- 9% in HPDG (P < 0.05); and proteinuria was 61.1 +/- 25 mg/24 h in LPDG, 218.7 +/- 27.5 mg/24 h in NPDG, and 324.5 +/- 64.8 mg/24 h in HPDG (P < 0.05). In Experiment II, at sacrifice, 24-h proteinuria was 189 +/- 16.1 mg in ADR, and 216 +/- 26.1 mg in ADR-ENA (P > 0.05); the tubulointerstitial lesion index was 5 for ADR, and 5 for ADR-ENA (P > 0.05); the frequency of glomerulosclerosis was 40 +/- 5.2% in ADR and 44 +/- 6% in ADR-ENA (P > 0.05); the amount of 131I-ferritin in the mesangium was 214.26 +/- 22.71 cpm/mg protein in ADR and 253.77 +/- 69.72 cpm/mg protein in ADR-ENA (P > 0.05). In Experiment III, sequential histological analysis revealed an acute tubulointerstitial cellular infiltrate at week 4, which was decreased at week 8. Tubular casts and dilatation were first seen at week 8 and increased at week 16 when few glomerular lesions were found.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Effects of dietary protein, angiotensin I converting enzyme inhibition and mesangial overload on the progression of adriamycin-induced nephropathy. 758 Oct 27

A 9-year-old boy with typical features of congenital erythropoietic porphyria who had received more than 50 blood transfusions developed the steroid-resistant nephrotic syndrome in the presence of normal glomerular function and glucosuria. Renal biopsy showed focal segmental glomerulosclerosis and widespread iron deposits. Magnetic resonance scanning revealed advanced siderosis of liver and kidneys. During a 4 year treatment by desferrioxamine the serum ferritin level was reduced, proteinuria dropped and serum proteins increased whilst glomerular filtration decreased slowly. It is suggested that the nephrotic syndrome may be a consequence of renal siderosis amenable to iron-chelating therapy.
 ...
PMID:Congenital erythropoietic porphyria associated with nephrotic syndrome and renal siderosis. 858 Jun 39

In two genetic models of "classic" focal segmental glomerulosclerosis (FSGS), the Milan normotensive and the Fawn-hooded hypertensive rats, tracer studies were performed to test the hypothesis that misdirected glomerular filtration and peritubular filtrate spreading are relevant mechanisms that contribute to nephron degeneration in this disease. Two exogenous tracers, lissamine green and horse spleen ferritin, were administered by intravenous injection and subsequently traced histologically in serial kidney sections. In contrast to control rats, both tracers in kidneys of Milan normotensive and Fawn-hooded hypertensive rats with established FSGS were found to accumulate extracellularly at the following sites: (1) within tuft adhesions to Bowman's capsule and associated paraglomerular spaces, (2) at the glomerulotubular junction contained within extensions of the paraglomerular spaces onto the tubule, and (3) within subepithelial peritubular spaces eventually encircling the entire proximal convolution of an affected nephron. This distribution strongly suggests the existence of misdirected filtration into tuft adhesions to Bowman's capsule and subsequent spreading of the filtrate around the entire circumference of a glomerulus and, alongside the glomerulotubular junction, onto the outer aspect of the corresponding tubule. This leads to an interstitial response that consists of the formation of a barrier of sheet-like fibroblast processes around the affected nephron, which confines the filtrate spreading and, subsequently, the destructive process to the affected nephron. No evidence was found that either misdirected filtration and peritubular filtrate spreading themselves or the associated tubulo-interstitial process led to the transfer of the injury from an affected nephron to an unaffected nephron. It is concluded that in the context of FSGS development, misdirected filtration and peritubular filtrate spreading are important damaging mechanisms that underlie the extension of glomerular injury to the corresponding tubulointerstitium, thus leading finally to degeneration of both the glomerulus and the tubule of a severely injured nephron.
 ...
PMID:Tracer studies in the rat demonstrate misdirected filtration and peritubular filtrate spreading in nephrons with segmental glomerulosclerosis. 1118 97

Factor H is the major complement regulator in plasma. Abnormalities in factor H have been implicated in membranoproliferative glomerulonephritis in both humans and experimental animals. It has been shown that factor H on rodent platelets functions analogously to human erythrocyte complement receptor 1 in its role to traffic immune complexes to the mononuclear phagocyte system. C57BL/6 factor H-deficient mice (Cfh(-/-)) and wild-type (wt) controls were immunized daily for 5 wk with heterologous apoferritin to study the chronic serum sickness GN model. Immunizations were started in 6- to 8-wk-old mice, which was before the development of spontaneous membranoproliferative glomerulonephritis in some Cfh(-/-) animals. Glomerular deposition of IgG immune complexes in glomeruli was qualitatively and quantitatively increased in Cfh(-/-) mice compared with wt mice. Consistent with the increase in glomerular immune complexes and possibly because of alternative pathway complement activation, Cfh(-/-) mice had increased glomerular C3 deposition. Wt mice developed no glomerular pathology. In contrast, Cfh(-/-) mice developed diffuse proliferative GN with focal crescents and glomerulosclerosis. In addition, there was significantly increased expression of collagen IV, fibronectin, and laminin mRNA in Cfh(-/-) glomeruli. These data show a role for platelet-associated factor H to process immune complexes and limit their accumulation in glomeruli. Once deposited in glomeruli, excessive complement activation can lead to glomerular inflammation and the rapid development of a scarring phenotype.
 ...
PMID:Complement factor h limits immune complex deposition and prevents inflammation and scarring in glomeruli of mice with chronic serum sickness. 1557 7


1 2 Next >>