Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033687 (proteinuria)
 24,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have recently reported that a lipid-lowering agent, probucol, reduces proteinuria in puromycin aminonucleoside (PA)-induced nephrotic rats (PAN). In this study, we examined whether a long-term treatment of hyperlipidemia with probucol can suppress the development of focal and segmental glomerulosclerosis (FSGS) in chronic PAN. A chronic PAN model was made with repeated intraperitoneal injections of PA (initially 100 mg/kg body weight followed by 25 mg/kg 5 times at 2-week intervals). Two weeks after the first injection of PA, either normal rat chow with or without 1% probucol was given to the nephrotic rats for 10 weeks. Chronic PAN exhibited remarkable proteinuria, hypoalbuminemia and severe hyperlipidemia with all lipoprotein fractions increased. Probucol treatment significantly reduced the lipid concentration in all major lipoproteins, significantly reduced proteinuria and increased plasma albumin concentration. Plasma albumin inversely correlated with cholesterol or phospholipid in low-density and high-density lipoproteins, suggesting that the lipid-lowering effect of probucol may ameliorate the hypoalbuminemia associated with nephrosis. In light microscopic examination, various degrees of FSGS with tubulointerstitial lesions were observed in the renal cortex from chronic PAN. The degree of FSGS was scored from grades 1 to 4 according to severity. One half of the untreated PAN (4/8) was classified into grade 4 and the other into grades 2 or 3, whilst one half of treated PAN (4/8) was classified either into grade 1 or 2. The grading of FSGS correlated negatively with plasma albumin concentration. These results demonstrate that probucol is highly effective upon nephrotic hyperlipidemia and suggest that a long-term treatment of secondary hyperlipidemia can suppress progressive renal injury associated with chronic nephrosis.
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PMID:Treatment of hyperlipidemia with probucol suppresses the development of focal and segmental glomerulosclerosis in chronic aminonucleoside nephrosis. 158 21

Change in the localization of the antigen recognized by the proteinuria-inducing monoclonal antibody (MA) 5-1-6 in experimental nephrosis was studied by indirect and biotin-avidin immunofluorescence, and immunoperoxidase at light and electron microscopical levels. The proteinuric state was induced by the administration of the aminonucleoside of puromycin (PAN) or adriamycin. The antigen decreased in quantity and/or its distribution changed with an increase in the amount of protein excreted in both experimental models. Recovery from the alterations observed during the development and proteinuria appeared to occur when PAN-induced proteinuria subsided. This antigenic molecule may thus be essential for maintaining the normal permselectivity of glomerular capillary walls.
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PMID:Altered localization of antigen recognized by proteinuria-inducing monoclonal antibody in experimental nephrosis. 167 76

The acute and chronic effects of daily, oral ciclosporin (CS) therapy (25 mg/kg) on proteinuria, blood pressure, renal function and histology were studied in rats subjected to unilateral nephrectomy and 3 weekly intraperitoneal injections of the aminonucleoside of puromycin (PAN). PAN therapy resulted in heavy proteinuria by week 4 which declined by weeks 8 and 16. When CS therapy was started weeks after the last dose of PAN, acute, transient reductions in proteinuria and reversible rises in blood urea nitrogen (BUN) were observed. When CS or oil therapy was started with PAN and continued for 8 or 16 weeks, there were no differences in proteinuria; however, after 16 weeks, CS treated rats had significantly higher BUN levels [65 +/- 11 (23.2 +/- 3.9) vs. 41 +/- 5 mg/dl (14.6 +/- 1.8 mmol/l); p = 0.001], a higher percentage of sclerotic glomeruli (47 +/- 7 vs. 28 +/- 10%; p less than 0.0001) and extensive interstitial fibrosis. There was a strong correlation between glomerulosclerosis and extent of interstitial fibrosis (r = 0.951; p less than 0.0001). These studies demonstrate that rats with experimental focal glomerulosclerosis treated with CS show an acute, transient reduction in proteinuria; however, chronic (for 16 weeks) CS therapy significantly increases azotemia and results in an increase in glomerulosclerosis and interstitial fibrosis.
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PMID:The effects of ciclosporin in experimental glomerulosclerosis. 208 1

This study deals with the quantification of mRNA of basement membrane components (laminin, type IV collagen, heparan sulfate proteoglycan) and type I collagen in focal glomerular sclerosis induced by the aminonucleoside of puromycin (PAN) in rats. PAN (15 mg/100 g B.W.) was injected intraperitoneally to male Sprague-Dawley rats on day 0. On day 22, the right kidney was removed from group II and III. Rats in group III received injections of PAN (5 mg/100 g B.W.) on day 27, 34 and 41. Rats in group II received injections of 0.9% NaCl instead of PAN. Remnant kidneys were removed on days 48, 60 and 80 and processed for RNA isolation and histopathological study. Glomerular RNAs were isolated using guanidinium thiocyanate and then dotted onto nylon membrane. Filters were hybridized with specific cDNA probes and exposed to film for analysis by densitometer. FGS was detected in 70% of glomeruli on day 80 in group II. All the basement membrane components and type I collagen were accumulated in the sclerotic areas. The mRNA coding for laminin and type IV collagen continued to increase in group III till day 80. The mRNA for HSPG decreased when the urinary protein excretion was maximum on day 48, then increased with the remission of proteinuria. The type I collagen mRNA also increased during the course of the FGS. We suggest that decrease of mRNA for HSPG may play an important role in the development of proteinuria in PAN nephrosis and increase of mRNA coding for laminin, type IV collagen and type I collagen may be involved in focal glomerular sclerosis.
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PMID:[Changes in the expression of basement membrane and type I collagen gene in focal glomerular sclerosis (FGS)]. 208 58

The administration of the aminonucleoside of puromycin (PAN) to rats causes the nephrotic syndrome that is associated with an acute decline in renal function, and an interstitial infiltrate. We examined whether essential fatty acid deficiency (EFAD), which inhibits macrophage infiltration in glomerulonephritis, affects PAN-induced renal dysfunction. Both control and EFAD rats developed proteinuria that resolved over 28 d. After PAN administration, there was a prominent infiltration of macrophages in rats fed a normal diet. The infiltrate was prevented by the EFAD diet. The absence of a macrophage interstitial infiltrate was associated with a significantly higher Cin in the EFAD rats than in controls at 7 d (5.21 +/- 1.19 versus 0.39 +/- 0.08, P less than 0.002 ml/min/kg BW). In addition, CPAH fell to less than 10 ml/min/kg BW by day 7 in controls, but remained the same as normal in the EFAD. After administration of PAN to control rats, there was no increase in urinary thromboxane excretion or an increase in glomerular thromboxane production. Furthermore, the effect of EFAD could not be mimicked by the administration of a thromboxane synthase inhibitor. Irradiation-induced leukopenia in rats on a normal diet markedly improved glomerular filtration and renal blood flow in acutely nephrotic rats. EFAD prevents the interstitial cellular infiltrate and the renal ischemia associated with experimental nephrosis. The recruitment of mononuclear cells into the kidney following PAN directly contributes to the decline in renal function.
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PMID:Essential fatty acid deficiency ameliorates acute renal dysfunction in the rat after the administration of the aminonucleoside of puromycin. 221 2

Rats receiving a single injection of either aminonucleoside of puromycin (PAN, 10 mg/100 g) or Adriamycin (ADR, 7.5 mg/kg) develop heavy proteinuria and tubulointerstitial nephritis. Interstitial mononuclear cells were markedly more intense in PAN- than in ADR-treated rats. The composition of cell infiltrates was characterised in frozen kidney sections using an immunoperoxidase staining method and a panel of specific monoclonal antibodies. The severe mixed cellular lesions observed in the PAN model on day 14 were dominated by ED1+ macrophages, OX6+ Ia-interstitial and OX8+ T-cytotoxic/suppressor cell surface markers. A similar but more discrete ADR-interstitial cell accumulation was observed on day 11 of the experiment. A correlation existed in the PAN model between the severity of interstitial nephritis and the degree of proteinuria. In contrast, there was no such correlation in ADR nephrosis. Administration of PAF antagonist (BN 52021), started on the first day and continued throughout the 4 weeks of the experiment, induced in both ADR and PAN-treated rats a partial reduction in the number of interstitial cell infiltrates. Glomeruli from normal control rats incubated with 3H acetate, substrate for lyso-PAF: acetyl-CoA acetyltransferase and ADR stimulated PAF generation. Although the precise mechanism of interstitial cell accumulation in these two models of nephrosis are still unknown, our results suggest that PAF could be an important factor involved in interstitial cell recruitment.
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PMID:Interstitial mononuclear cell infiltrates in experimental nephrosis: effect of PAF antagonist. 251 24

The aminonucleoside of puromycin (PAN) induces nephrotic syndrome in rats. We studied the tubulointerstitial cellular (TIC) infiltrate previously unrecognized in this model. Rats received one i.p. injection of PAN (15 mg/100 g) and were sacrificed at 1, 3, 4, 5, 7, 14, 20 and 28 days. Frozen kidney sections and peripheral blood cells were stained with a panel of anti-rat monoclonal antibodies and quantitated by epifluorescence microscopy. An increase in Ia+ cells (60/1000 TIC) (P less than 0.001) and OX42+ macrophages (MO) (18/1000 TIC) (P less than 0.05) were observed on day 5. On day 7 the infiltrate consisted of OX19+ T-lymphocytes (29/1000 TIC) (P less than 0.001) and OX42+ MO (68/1000 TIC) (P less than 0.001). The majority of the lymphocytes expressed the OX8 cytotoxic T cell marker (23/1000 TIC) (P less than 0.001). The severe mixed cellular lesion present on day 14 was dominated by OX42+ MO (113/1000 TIC) (P less than 0.001). With resolution of proteinuria on days 20 and 28, the infiltrate decreased, although OX42+ MO persisted on day 28 (46/1000 TIC) (P less than 0.001). The severity of the cellular lesion correlated with the degree of albuminuria (r = 0.57 to 0.81 for the antibody panel). Expression of Ia antigens by proximal tubular epithelial cells markedly decreased during peak proteinuria but normalized by day 28. Increased deposition of C3 and IgG was not detected. Reversible tubulointerstitial nephritis develops in PAN-treated rats and may be a consequence of severe proteinuria.
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PMID:Acute tubulointerstitial nephritis associated with aminonucleoside nephrosis. 325 89

Alterations of glomerular basement membrane (GBM) anionic (charge sites, CSs) in the development of proteinuria in a model of idiopathic nephrotic syndrome in man (puromycin aminonucleoside nephrotic syndrome [PAN] in the rat) were assessed quantitatively and sequentially early after disease induction. GBM CSs (known to consist mainly of heparan sulfate-rich proteoglycans) were stained in vivo and, in a separate group of animals by an in vitro method, with the cationic marker polyethyleneimine (PEI) studied by electron microscopic examination. Four hours after administration of PAN, there was a significant decrease in GBM lamina rara externa CSs: 18 +/- 0.7 versus 22.0 +/- 2.2 per 1000 nm GBM in controls by PEI injection and 17.2 +/- 2.7 versus 21.1 +/- 1.6 per 1000 nm GBM in controls by PEI in vitro staining. This CS alteration coincided with changes in glomerular epithelial cell morphologic characteristics (increased cytoplasmic organelles and rough endoplasmic reticulum) and preceded the detection of foot process broadening (at 24 hours) and increased urinary albuminuria (suggested at 12-24 hours, statistically significant at 36-48 hours). These results suggest that GBM CS-heparan sulfate proteoglycan alterations consisting of either decreased number and/or less anionic charge occur early in PAN and support a role for glomerular epithelial cell maintenance of GBM CS for normal glomerular function.
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PMID:Glomerular basement membrane anionic charge site changes early in aminonucleoside nephrosis. 378 94

Glomerular epithelial cells (GECs) in vitro provide a useful model for the study of the mechanism(s) underlying the nephrotic syndrome of rats induced by the aminonucleoside of puromycin (PAN). Some of the toxicities of PAN are nonspecific, in that the constituent molecules of PAN (adenosine and puromycin) cause similar effects in vitro. These include GEC blebbing and rounding, reduced uptake of precursors of protein (leucine) and glycoprotein (glucosamine) synthesis, and increased permeability of the GEC membrane to adenosine. Some of the effects of PAN are not reproduced by adenosine or puromycin and are inhibited by the simultaneous presence of N6-monomethyl adenosine (MMA), a PAN analog and an in vivo blocker of nephrosis due to PAN. These processes may be related to the nephrotic syndrome and include the loss of adhesion to plastic; a reduction in the incorporation of 14C-glucosamine and 35S-sulfate both into molecules removable from the GEC surface by neuraminidase and into those moieties precipitated from the culture media by TCA; a marked reduction in the "ordering" of the lipids of the rigid GEC membrane, which is possibly dependent upon cell-surface proteins. These morphologic alterations in GECs and in the distribution of negatively charged molecules, which are either secreted or on the cell surface, correlate with observations made in PAN-induced nephrosis in rats in vivo. These include changes in the turnover and the array of sialic acid and heparan sulfate glycoprotein on the GECs and the glomerular basement membrane. The in vitro sensitivity of GECs to PAN and the effects of MMA suggest a role for these cells in in vivo aminonucleoside nephrotoxicity, where alterations in both the morphology and the anionic topology of GECs participate in the development of proteinuria.
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PMID:Effects of the aminonucleoside of puromycin on glomerular epithelial cells in vitro. 397 43

Puromycin aminonucleoside (PA), injected intravenously into rats in a single dose, causes proteinuria and ultrastructural pathology reminiscent of human lipoid nephrosis (puromycin aminonucleoside nephrosis (PAN]. Glomerular epithelial cell (GEC) endocytosis was studied in this model and in rats with protein-overload proteinuria using ultrastructural morphometry. Disappearance curves were constructed for protamine-heparin aggregates (PHA), which localized in the subepithelial region of the glomerular basal lamina following intravenous injection of protamine followed by heparin. Five groups were studied: (a) preproteinuric PAN, 4 days after PA (mean 4.5 +/- 1.5 mg of urinary protein/24 hours); (b) proteinuric PAN, 10 days after PA (mean 128 +/- 9.6 mg/24 hours); (c) recovery from PAN (mean 12.5 +/- 1.5 mg/24 hours); (d) protein-overload proteinuria, induced by injecting albumin intraperitoneally (mean 211 +/- 15.9 mg/24 hours); and (e) saline-injected controls (mean 1.2 +/- 0.2 mg/24 hours). Only the proteinuric PAN animals (group 2) had altered GEC endocytosis with a PHA half-disappearance time different from the group 5 saline controls (143.2 versus 72.6 minutes, p less than 0.05). The half-disappearance times in groups 1, 3, and 4 were 74.6, 80.7 and 86.5 minutes, respectively. Altered GEC function was further characterized by comparing PHA disappearance with the abundance of albumin-filled vacuoles in the GEC. Prolongation of PHA disappearance in group 2 correlated with the virtual absence of vacuoles; they were abundant in nonproteinuric phases of PAN and in animals with overload proteinuria. We conclude (a) GEC endocytosis is reduced only during the proteinuric phase of PAN, (b) GEC endocytosis is active during the preproteinuric phase of PAN and is a factor that may account for the absence of protein in the urine despite abnormal GBM permeability, (c) decreased GEC endocytosis during proteinuric PAN reflects abnormal cell metabolism due to PA and is not simply a consequence of albuminuria, as overload proteinuria did not produce diminished PHA or albumin uptake.
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PMID:Inhibition of glomerular visceral epithelial cell endocytosis during nephrosis induced by puromycin aminonucleoside. 638 77


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