Vitamin A-deficient rats have low levels of retinol-binding protein (RBP) in serum and elevated levels of RBP in their livers. Chylomicrons containing newly absorbed vitamin A were injected intravenously into vitamin A-deficient rats, and the levels of vitamin A and of RBP in serum were determined on samples collected serially from individual rats. Data were also obtained on liver immunoreactiv...

Abstract Introduction Transthyretin (TTR) is a homotetrameric 55-KDa plasma protein that transports thyroxin and retinol complexed to retinol-binding (RBP). TTR misfolding aggregation can lead the extracellular deposition of amyloid (ATTR) representing one most frequent forms amyloidosis in elderly. Aim this study develop native electrophoretic method characterize circulating samples ATTR patie...

BACKGROUND Prospective studies in humans examining the effects of fructose consumption on biological markers associated with the development of metabolic syndrome are lacking. Therefore we investigated the relative effects of 10 wks of fructose or glucose consumption on plasma uric acid and RBP-4 concentrations, as well as liver enzyme (AST, ALT, and GGT) activities in men and women. METHODS ...

Vitamin A circulates in human plasma as retinol bound to a specific transport protein. This protein differs from the known low and high density plasma lipoproteins and has a hydrated density greater than 1.21. In order to study this protein, volunteers were injected intravenously with retinol-15-(14)C. Plasma was collected 1-3 days later, and the purification of retinol-binding protein (RBP) wa...

We have previously reported that interleukin 4 (IL-4) inhibits the growth of human gastric carcinoma cells. To investigate the mechanism for this inhibition we analyzed the effect of IL-4 on cell cycle progression of the IL-4-sensitive gastric carcinoma cell line, HTB-135. IL-4 significantly inhibited cell cycle Gt-S-phase progression. To assess the postreceptor molecular events that transduced...

The membrane receptor for retinol-binding protein (RBP) has been solubilized from human placental brush-border membranes with octyl-beta-glucoside, Nonidet P-40 and CHAPS. A method, based on the preferential precipitation of 125I-RBP-receptor complex with poly(ethylene glycol) 8000, was developed in order to measure the RBP-binding activity in the detergent extracts. The receptor was fairly sta...

Levels of retinol-binding (RBP), the plasma transport protein for vitamin A, were measured by radioimmunoassay in sera and in a large number of tissues from both normal and vitamin A-deficient rats. The tissues included liver, kidney, fat, muscle, brain, eye, salivary gland, thymus, lung, heart, intestine, spleen, adrenal, testes, thyroid, and red blood cells. The RBP levels in tissues other th...

Riboflavin-binding protein (RBP) and phosvitin are phosphoglycoproteins transferred from the plasma of laying hens into the yolk of developing oocytes. We have examined the effect of phosphate removal on this yolk deposition process. Unmodified yolk RBP and phosvitin contain, respectively, 8.3 and 109 residues of phosphate/molecule. Complete dephosphorylation of yolk RBP caused a 20-min decreas...

Bovine and human retinol-retinol-binding protein (RBP) were iodinated to high specific activity. At least 34% of the iodinated material was native and retained its retinol chromophore as judged by its characteristic ability to bind to plasma prealbumin. Bovine and human retinol-125I-RBP were found to bind specifically to intact isolated pigment epithelium cells from bovine eyes. The specific bi...