Serum and urinary lipoproteins in the human nephrotic syndrome: evidence for renal catabolism of lipoproteins

Journal Article · Mon Mar 01 00:00:00 EST 1982 · Metabolism; (United States)

DOI:https://doi.org/10.1016/0026-0495(82)90062-2· OSTI ID:6816302

Shore, V G; Forte, T; Licht, H; Lewis, S B

The urinary excretion of lipoproteins and the possibility of catabolic alterations on glomerular filtration were investigated in four nephrotic subjects difering in etiology, serum lipoprotein profile, and 24 hr urinary output of protein and lipids. The apolipoproteins and lipoproteins of urine were compared with those of serum with respect to distribution profile, physical properties, and composition. As expected from molecular sieving effects during glomerular filtration, the urinary HDL were more abundant than the lower density lipoproteins even when the plasma LDL was elevated markedly. Intact apolipoproteins were not found in the concentrated urinary fraction isolated by ultrafiltration between the limits of 10/sup 4/ and 5 x 10/sup 4/ daltons. On the basis of immunoreactivity, gel electrophoresis, and amino acid composition, apolipoproteins B and AI are the major and minor proteins, respectively, of urinary LDL, and apo B is the major protein of the urinary IDL and VLDL. Apolipoproteins AI, AII, CI, CIII, and possibly AIV were isolated from the urinary HDL. As much as 20% of the protein moiety of the urinary HDL appeared to be large apolipoprotien fragments with molecular weights and isoelectric points similar to those of apo CII and apo CIII. The lower density classes of urinary lipoproteins also appeared to have lost apo E and apo C's and to have undergone partial proteolysis.

• Research Organization: Lawrence Livermore National Lab., CA
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6816302
• Journal Information: Metabolism; (United States), Vol. 31:3
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
LIPOPROTEINS
CATABOLISM
ULTRAFILTRATION
NEPHRITIS
PATHOLOGY
BIOCHEMISTRY
BLOOD SERUM
EXCRETION
GLOMERULI
PATIENTS
URINE
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
BODY
BODY FLUIDS
CHEMISTRY
CLEARANCE
DISEASES
FILTRATION
KIDNEYS
LIPIDS
MATERIALS
METABOLISM
ORGANIC COMPOUNDS
ORGANS
PROTEINS
SEPARATION PROCESSES
UROGENITAL SYSTEM DISEASES
WASTES
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