The acute inflammatory response to tissue injury and infection is associated with low concentrations of plasma retinol and its specific transport proteins, retinol-binding protein (RBP) and transthyretin (TTR). To examine the kinetics and mechanism of hyporetinemia, we have induced acute inflammation with lipopolysaccharide (LPS, from Pseudomonas aeruginosa) in rats with adequate stores of vita...

A comparative study of the interactions of rat cellular retinol-binding protein (CRBP) and cellular retinol-binding protein II (CRBP II) with a number of synthetic phenyl-substituted analogs of all-trans-retinol was performed using fluorescence and nuclear magnetic resonance analysis. These studies indicate that CRBP II is more sensitive to modifications of the ring moiety than CRBP. Removal of...

To assess the effect of zinc supplementation on plasma retinol levels, 24 preterm infants were randomly assigned to receive 400 micrograms.kg-1.d-1 of intravenous Zn or no Zn supplementation. Intakes of protein, energy, and vitamin A were similar for both groups as were day 0 plasma concentrations of retinol, retinol-binding protein (RBP), and Zn. Zn concentrations were not significantly differ...

Retinol and its derivative, retinoic acid, have pleiotropic functions including vision, immunity, hematopoiesis, reproduction, cell differentiation/growth, and development. Non-alcoholic fatty liver disease (NAFLD) is one of the most common diseases in developed countries and encompasses a broad spectrum of forms, ranging from steatosis to steatohepatitis, which develops further to cirrhosis. R...

Retinol-binding protein (RBP) is the sole specific transport protein for retinol (vitamin A) in the circulation, and its single known function is to deliver retinol to tissues. Within tissues, retinol is activated to retinoic acid, which binds to nuclear receptors to regulate transcription of >300 diverse target genes. In the eye, retinol is also activated to 11-cis-retinal, the visual chromoph...

Background & Objective: Diabetic retinopathy (DR) is a common microvascular complication of type 2 diabetes mellitus (T2DM) and the leading cause of vision loss in working-age adults. Vitamin A (retinol) has a role in the mechanism of vision process and retinol binding protein-4 (RBP4), is a carrier of vitamin A, and as an adipokine may be associated with increased risk for insulin resistance a...

We discuss here both previously published data and our current experiments which suggest that the vitamin A derivative, retinoic acid (RA), may play a role in the development of the vertebrate central nervous system (CNS). This evidence comes from the following: both an excess and a deficiency of vitamin A causes embryonic defects of the CNS; RA has been detected endogenously in the CNS; RA sti...

As a model of ligand-dependent protein secretion the biosynthesis, intracellular transport, and release of the retinol-binding protein (RBP) were studied in primary cultures of rat hepatocytes pulse-labeled with [35S]methionine. After various periods of chase RBP was isolated by immunoprecipitation and identified by SDS PAGE. Both normal and vitamin A-deficient hepatocytes synthesized RBP. The ...

Cellular retinol-binding protein (CRBP) has been purified to homogeneity from normal human liver. The procedures in the purification involved primarily gel filtration and ion exchange chromatography, resulting in a 3000-fold purification with greater than 40% yield. The protein is a single:polypeptide chain with molecular weight of 14,800. The protein binds retinol in a manner which considerabl...