Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020639 (hypoproteinemia)
 1,134 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Intravenous administration of the aminonucleoside of puromycin produces the nephrotic syndrome (proteinuria, hypercholesterolemia, hypoproteinemia and edema) in rats. This model is very similar to human nephrotic syndrome caused by various disease states. The current study was designed to assess the nature of urinary lipoproteins in the urine of nephrotic rats, including studies related to the urinary loss of the "activator" apolipoproteins for the lipoprotein lipase-triglyceride interaction. Sprague-Dawley rats were given a single intravenous injection (10 mg/100 g) of puromycin aminonucleoside. Plasma and urine were collected before and 7, 18, 29, 36, and 53 days after injection of puromycin. Urine was fractionated in the preparative ultracentrifuge into density (d) fractions less than 1.006 (very low-density lipoproteins), d = 1.006-1.063 (low-density lipoproteins), and d = 1.063-1.210 (high-density lipoproteins--HDL). The cholesterol, triglyceride, phospholipid, and protein content of these fractions was analyzed. Lipoprotein electrophoresis was performed in agarose agar. Urine from normal and nephrotic rats was added to an in vitro system containing lipoprotein lipase and triglyceride. The free fatty acids (FFA) liberated were then measured as an index of urinary activator property on this system. Measurable urinary lipoproteins were present only on days 7 and 18 after induction of the nephrotic syndrome. Coelectrophoresis of these urinary lipoproteins with rat plasma revealed a single band having alpha- (HDL) electrophoretic mobility. The total mean protein content of day-7 urinary lipoproteins (64.3%) was greater than the content of plasma HDL (52.9%). The protein content of urinary lipoproteins also increased with time. When day-7 and day-18 postinjection urine at nephrotic rats was added to the lipoprotein lipase system, the hydrolysis of triglyceride yielded a mean of 0.320 and 0.235 muEq FFA/ml/20 min, respectively. Control rat urine yielded 0.030 muEq FFA/ml/20 min and 0.000 muEq FFA/ml/20 min 7 and 18 days after injection of normal saline, respectively. It is inferred that in this experimental model (1) high-density lipoproteins are probably excreted in the glomerular filtrate, (2) alterations in the composition of the excreted lipoproteins may occur during their passage through the nephron. The possibility that only a selective portion of the HDL spectrum is excreted into the glomerular filtrate cannot be excluded. It is suggested that the urinary or renal loss of this functionally important lipoprotein may contribute to the pathophysiology of hyperlipoproteinemia in the nephrotic syndrome.
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PMID:High density lipoproteinuria in nephrotic syndrome. 18 67

Triamcinolone or triiodothyronine (T3) was administered to rats with nephrosis induced by aminonucleoside of puromycin and to control nontreated rats. Triamcinolone produced hyperglycemia, hyperinsulinemia and liver glycogen deposition in control rats and to a lesser extent in nephrotic rats. Triamcinolone treatment did not affect plasma protein and albumin levels but increased the level of plasma triglycerides and cholesterol in the very low density lipoprotein (VLDL) and LDL but not high density lipoprotein fractions. The exacerbation of hyperlipoproteinemia was attributed both to increase hepatic lipid synthesis and delayed removal, since it was associated with the induction of hepatic acetyl-CoA carboxylase, the regulatory enzyme of lipogenesis, as well as with marked suppression of adipose tissue lipoprotein lipase (LPL). The hepatic lipase activity was found to be elevated in nephrotic rats but was suppressed by triamcinolone treatment, indicating a reduced capacity of VLDL to LDL conversion. T3 treatment resulted in serum glucose and insulin increases similar to triamcinolone, but more moderate in nephrotic vs. control rats, and in marked reduction in liver glycogen content. Plasma protein levels were not affected, but contrary to control rats, T3 treatment produced an elevation in serum triglycerides and cholesterol in nephrotic rats. The activity of several hepatic lipogenic enzymes, including acetyl-CoA carboxylase, was markedly elevated, as was the activity of gluconeogenic enzymes. Thus, the hyperlipoproteinemia on T3 treatment appeared to be mainly due to predomination of lipid synthesis over removal, since the activities of enzymes responsible for plasma lipid disposal, adipose tissue LPL and hepatic lipase were enhanced both in control and nephrotic rats. It is remarkable that both T3 and triamcinolone induce the lipogenic enzymes and apolipoproteins in the liver of nephrotic rats, already pronouncedly stimulated to replace the excreted plasma proteins. Thus, the nephrotic liver is able to respond to hormonal stimulation with further specific protein and lipid synthesis. It is also pertinent that the recovery from immunosuppressive treatment of human nephrosis, developing on an immune background, may result in more impressive amelioration of proteinuria and hypoproteinemia than of hyperlipoproteinemia because of the lipidemic effect of glucocorticoids.
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PMID:Hyperlipoproteinemia of aminonucleoside-induced nephrotic syndrome--modulation by glucocorticoids and triiodothyronine. 868 44

It is well known that patients with diabetes have a high incidence of cardiovascular disease (CVD), and the incidence of CVD becomes substantially elevated with development of diabetic nephropathy. The mechanisms for dyslipidemia in diabetic nephropathy are multifactorial and complex. Long-term hyperglycemia causes generalized vascular endothelial damage, which reduces functional lipoprotein lipase, leading to increased triglyceride (TG) levels and decreased high-density lipoprotein cholesterol (HDL-C). In overt-diabetic nephropathy, hypoproteinemia markedly increases low-density lipoprotein cholesterol (LDL-C), and renal failure specifically increases remnant lipoproteins and decreases HDL-C and LDL-C. Overt diabetic nephropathy exhibits remarkable postprandial hypertriglyceridemia with hyper-apolipoprotein (apo) B48, a marker of chylomicron and its remnants. Apo CIII is a key inhibitor of lipolysis and particle uptake of TG-rich lipoproteins, which is specifically increased in advanced chronic kidney disease, irrespective of the presence of diabetes. LDL size becomes smaller with advanced stages of diabetic nephropathy, whereas LDL size is not reduced in hemodialysis patients (HD). HD patients have marked lower levels of HDL3-C than controls. HD patients also have substantially low apo AI and high serum amyloid A (SAA) levels, suggesting the replacement of apo AI by SAA is stimulated in HDL particles.
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PMID:Abnormal lipoprotein metabolism in diabetic nephropathy. 2413 62