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

High dietary protein intake, in the past recommended for nephrotic syndrome, does not improve hypoproteinemia and may accelerate progressive renal damage. In contrast, low-protein diets reduce proteinuria and preserve renal function in experimental renal models of nephrotic syndrome. In this study, 20 steroid-resistant, nephrotic patients were treated with a pure vegetarian, low-protein diet, supplemented with essential amino acids and ketoanalogues (supplemented vegan diet, SVD) for 4.6 +/- 3.1 months. Before the study, these patients followed an unrestricted protein, low-sodium diet (LSD). Proteinuria, daily urea nitrogen excretion and creatinine clearance decreased significantly on SVD. A similar lowering effect of SVD was observed on serum total cholesterol. Seven of the 20 patients changed from LSD to SVD and vice-versa on 3 occasions, and in all cases, we found an increase of proteinuria during the LSD period. Serum albumin, HDL cholesterol, triglycerides and anthropometric measurements did not change on SVD. Our data suggest that SVD exerts a favorable effect on proteinuria and hypercholesterolemia in nephrotic patients, without inducing clinical or laboratory signs of malnutrition.
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PMID:A special, supplemented 'vegan' diet for nephrotic patients. 180 35

Mesenteric lymph was collected for 48 h from rats with aminonucleoside-induced nephrotic syndrome, receiving an intraduodenal infusion of a triacylglycerol emulsion. In nephrosis, the rates of lymph flow and triacylglycerol transport were approx. 2-fold higher, but the transport of total protein and of apoproteins A-I and E was 2- to 3-fold lower than that in control rats, resulting in chylomicrons with a 3-fold approx. elevated triacylglycerol/protein ratio. Supplementation of the triacylglycerol infusate with glucose and amino acids did not increase the protein or apoA-I and apoE transport. Production or transport of B and C apoproteins in nephrotic rats was also reduced, as indicated by tetramethylurea solubility, incorporation of intraduodenally infused [3H]leucine and staining of the chylomicron proteins on SDS-PAGE gels. Apoprotein A-IV was the only chylomicron component into which the leucine incorporation was elevated, but its relative content was not increased on SDS-PAGE gels. Lymph chylomicrons of nephrotic rats were larger in size (1498 +/- 37 vs. 1235 +/- 23 A), consistent with the higher triacylglycerol/protein ratio. The concentration of all lipoprotein classes was markedly elevated in the plasma of nephrotic rats, as was that of the total A-I and E apoproteins. Intravenous injection of 125I-labelled HDL, followed by tracing of the label in lymph chylomicrons, indicated a lower rate of transfer of HDL apoproteins from plasma to lymph in nephrotic rats. We conclude that the intestinal chylomicron formation in nephrosis is characterised by an enhanced triacylglycerol transport without the appropriate apoprotein complement. This is probably due to the limited capacity of enterocytes, in marked contrast to hepatocytes, to respond to the hypoproteinemia of nephrosis with increased production and/or transport of the apoproteins.
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PMID:Chylomicron synthesis in experimental nephrotic syndrome. 277 59

Lipids of the blood serum were studied in 29 patients with untreated nephrotic syndrome (NS) and in 28 patients treated with corticosteroids or nonsteroid drugs. None of the patients had evidence of renal failure, either acute or chronic. The patients with untreated NS showed massive proteinuria, marked hypoproteinemia, considerable hypertriglyceridemia and hypercholesterolemia. Serum high-density lipoprotein cholesterol (HDL cholesterol) concentrations were lower in these patients than in the control group, including 35 normal subjects, and correlated with the total serum protein (r = 0.46, p less than 0.05) and serum albumin (r = 0.46, p less than 0.05). An inverse correlation was observed between HDL cholesterol and serum triglyceride levels (r = -0.58, p less than 0.01). In the treated patients the laboratory indices of NS were less pronounced. HDL cholesterol levels were within normal limits in 14 patients with NS treated mostly with nonsteroid drugs, while in the patients receiving the corticosteroids (14 subjects) they were significantly higher than in the control group.
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PMID:High-density lipoprotein cholesterol in patients with untreated and treated nephrotic syndrome. 671 5

Livers from rats with experimental hypoproteinemia induced by aminonucleoside-nephrosis or plasmapheresis were perfused with a [14C]-labeled amino acid mixture at physiological concentration. Compared to control rats, a significantly increased incorporation of the amino acid label was found in the apolipoproteins of the ultracentrifugally separated very low and high density lipoproteins (VLDL, HDL), and into albumin secreted into the perfusate. However, no increase in the amino acid-derived lable was detected in VLDL-or HDL-borne lipids in nephrosis or plasmapheresis. Perfusion with U-[14C]leucine as a lipogenesis precursor at < 10 times higher than physiological concentration resulted in 5-fold increase in the label incorporation into perfusate proteins in nephrosis but only in a slightly significant increase in perfusate lipids. In contrast, the incorporation of a preformed fatty acid, 9,10-[3H] oleate into VLDL and HDL lipids increased 3- to 4-fold in nephrosis. Both with leucine and oleate as precursors, the increments in the label appearing in perfusate proteins or lipids, respectively, were markedly greater than the increases in hepatic tissue proteins or lipids. The results indicate that amino acids are preferentially directed by the liver into the synthesis of circulating apolipoproteins and albumin in hypoproteinemia and do not seem to constitute an important precursor of the liporpotein lipids. The increased production of apolipoproteins is associated with an increased incorporation of preformed fatty acids into lipoprotein lipids in addition to the previously reported stimulation of hepatic de novo lipid synthesis from recursors other than amino acids.
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PMID:Lipoprotein lipid and protein synthesis in experimental nephrosis and plasmapheresis: II. Perfused rat liver. 742 18

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

Coronavirus disease 2019 (COVID-19) is a global pandemic which has caused numerous deaths worldwide. The present study investigated the roles of hypoproteinemia in the clinical outcome and liver dysfunction of COVID-19 patients. In this retrospective study, we extracted data from 2,623 clinically confirmed adult COVID-19 patients (>18 years old) between January 29, 2020 and March 6, 2020 in Tongji Hospital, Wuhan, China. The patients were divided into three groups-non-critically ill, critically ill, and death groups-in accordance with the Chinese Clinical Guideline for COVID-19. Serum albumin, low-density lipoproteins cholesterol (LDL-C), and high-density lipoproteins cholesterol (HDL-C) concentrations and inflammatory cytokines levels were measured and compared among these three groups. The median age of these 2,623 patients was 64 years old (interquartile range (IQR), 52-71). Among the patients enrolled in the study, 2,008 (76.6%) were diagnosed as non-critically ill and 615 (23.4%) were critically ill patients, including 383 (14.6%) critically ill survivors and 232 (8.8%) critically ill deaths in the hospital. Marked hypoalbuminemia occurred in 38.2%, 71.2%, and 82.4% patients in non-critically ill, critically ill, and death groups, respectively, on admission and 45.9%, 77.7%, and 95.6% of these three groups, respectively, during hospitalization. We also discovered that serum low-density lipoprotein (LDL) and HDL levels were significantly lower in critically ill and death groups compared to non-critically ill group. Meanwhile, the patients displayed dramatically elevated levels of serum inflammatory factors, while a markedly prolonged activated partial thromboplastin time (APTT) in critically ill patients reflected coagulopathy. This study suggests that COVID-19-induced cytokine storm causes hepatotoxicity and subsequently critical hypoalbuminemia, which are associated with exacerbation of disease-associated inflammatory responses and progression of the disease and ultimately leads to death for some critically ill patients.
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PMID:Decreased serum albumin level indicates poor prognosis of COVID-19 patients: hepatic injury analysis from 2,623 hospitalized cases. 3256 3