Effect of Different Combinations of Dietary Vitamin A, Protein Levels, and Monensin on Inflammatory Markers and Metabolites, Retinol-Binding Protein, and Retinoid Status in Periparturient Dairy Cows

The objective of this study was to determine the effect of feeding different combinations of dietary vitamin A supplementation (0 or 110 IU/kg body weight), protein (10.3% or 12.2%), and an ionophore (monensin at 0 or 400 mg/day) on retinoid metabolism and immune function of dairy cows. Eighty multiparous Holstein dairy cows were studied from d −35 to +21 relative to expected parturition in a complete randomized block design with a 2 × 2 × 2 factorial arrangement of treatments. The significance of treatments was declared at p ≤ 0.05. Dairy cows receiving high crude protein (CP) diets with monensin had a greater retinol-binding protein serum concentration than cows receiving high CP diets without monensin (p = 0.04). Animals supplemented with vitamin A showed lower SCC (p = 0.04) and a higher thiobarbituric acid reactive substances concentration (p = 0.06) than cows non-supplemented. Moreover, cows receiving low crude protein diets had a greater haptoglobin concentration (p = 0.01). In addition, cows fed a high crude protein diet had a greater TNF-α expression in peripheral blood mononuclear cells (p = 0.04). Animals fed diets without monensin had a greater serum haptoglobin on day 3 postpartum than those fed monensin (p = 0.01). Moreover, dietary vitamin A increased serum 13-cis retinoic acid postpartum. We conclude that vitamin A, crude protein levels, and monensin fed during the close-up period affect milk somatic cell count, some vitamin statuses, and inflammatory markers during early lactation.

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Dietary Vitamin A and Visceral Adiposity: A Modulating Role of the Retinol-Binding Protein 4 Gene

Journal of Nutrigenetics and Nutrigenomics ◽

10.1159/000442090 ◽

2015 ◽

Vol 8 (4-6) ◽

pp. 164-173 ◽

Cited By ~ 7

Author(s):

Katie Goodwin ◽

Michal Abrahamowicz ◽

Gabriel Leonard ◽

Michel Perron ◽

Louis Richer ◽

...

Keyword(s):

Vitamin A ◽

Binding Protein ◽

Visceral Adiposity ◽

Retinol Binding Protein ◽

Dietary Vitamin ◽

Retinol Binding Protein 4

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Vitamin A Transporters in Visual Function: A Mini Review on Membrane Receptors for Dietary Vitamin A Uptake, Storage, and Transport to the Eye

Nutrients ◽

10.3390/nu13113987 ◽

2021 ◽

Vol 13 (11) ◽

pp. 3987

Author(s):

Nicasio Martin Ask ◽

Matthias Leung ◽

Rakesh Radhakrishnan ◽

Glenn P. Lobo

Keyword(s):

Cell Growth ◽

Vitamin A ◽

Visual Function ◽

Binding Protein ◽

Retinol Binding Protein ◽

Dietary Vitamin ◽

Peripheral Tissues ◽

Retinol Binding Protein 4 ◽

Retinyl Esters ◽

And Function

Vitamins are essential compounds obtained through diet that are necessary for normal development and function in an organism. One of the most important vitamins for human physiology is vitamin A, a group of retinoid compounds and carotenoids, which generally function as a mediator for cell growth, differentiation, immunity, and embryonic development, as well as serving as a key component in the phototransduction cycle in the vertebrate retina. For humans, vitamin A is obtained through the diet, where provitamin A carotenoids such as β-carotene from plants or preformed vitamin A such as retinyl esters from animal sources are absorbed into the body via the small intestine and converted into all-trans retinol within the intestinal enterocytes. Specifically, once absorbed, carotenoids are cleaved by carotenoid cleavage oxygenases (CCOs), such as Beta-carotene 15,15’-monooxygenase (BCO1), to produce all-trans retinal that subsequently gets converted into all-trans retinol. CRBP2 bound retinol is then converted into retinyl esters (REs) by the enzyme lecithin retinol acyltransferase (LRAT) in the endoplasmic reticulum, which is then packaged into chylomicrons and sent into the bloodstream for storage in hepatic stellate cells in the liver or for functional use in peripheral tissues such as the retina. All-trans retinol also travels through the bloodstream bound to retinol binding protein 4 (RBP4), where it enters cells with the assistance of the transmembrane transporters, stimulated by retinoic acid 6 (STRA6) in peripheral tissues or retinol binding protein 4 receptor 2 (RBPR2) in systemic tissues (e.g., in the retina and the liver, respectively). Much is known about the intake, metabolism, storage, and function of vitamin A compounds, especially with regard to its impact on eye development and visual function in the retinoid cycle. However, there is much to learn about the role of vitamin A as a transcription factor in development and cell growth, as well as how peripheral cells signal hepatocytes to secrete all-trans retinol into the blood for peripheral cell use. This article aims to review literature regarding the major known pathways of vitamin A intake from dietary sources into hepatocytes, vitamin A excretion by hepatocytes, as well as vitamin A usage within the retinoid cycle in the RPE and retina to provide insight on future directions of novel membrane transporters for vitamin A in retinal cell physiology and visual function.

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A Functional Binding Domain in the Rbpr2 Receptor is Required for Vitamin A Transport, Ocular Retinoid Homeostasis, and Photoreceptor Cell Survival in Zebrafish

10.20944/preprints202003.0296.v1 ◽

2020 ◽

Author(s):

Ashish K. Solanki ◽

Altaf A Kondkar ◽

Joseph Fogerty ◽

Yanhui Su ◽

Seok-hyung Kim ◽

...

Keyword(s):

Vitamin A ◽

Cell Survival ◽

Photoreceptor Cell ◽

Binding Protein ◽

Binding Domain ◽

Human Vision ◽

Retinol Binding Protein ◽

Dietary Vitamin ◽

Binding Residues ◽

Vitamin A Transport

Dietary vitamin A/all-trans retinol/ROL plays a critical role in human vision. ROL circulates bound to the plasma retinol-binding protein (RBP4) as RBP4-ROL. In the eye, the STRA6 membrane receptor binds to circulatory RBP4 and internalizes ROL. STRA6 is however not expressed in systemic tissues, where there is high-affinity RBP4 binding and ROL uptake. We tested the hypothesis, that the second retinol-binding protein 4 receptor 2 (Rbpr2) which is highly expressed in systemic tissues of zebrafish and mouse, contains a functional RBP4 binding domain, critical for ROL transport. As for STRA6, modeling and docking studies confirmed three conserved RBP4 binding residues in zebrafish Rbpr2. In cell culture studies, disruption of the RBP4 binding residues on Rbpr2 almost completely abolished uptake of exogenous vitamin A. CRISPR generated rbpr2-RBP4 domain zebrafish mutants showed microphthalmia, shorter photoreceptor outer segments, and decreased opsins, that were attributed to impaired ocular retinoid content. Injection of WT-Rbpr2 mRNA into rbpr2 mutant or all-trans retinoic acid treatments rescued the mutant eye phenotypes. In conclusion, zebrafish Rbpr2 contains a putative extracellular RBP4-ROL ligand-binding domain, critical for yolk vitamin A transport to the eye for ocular retinoid production and homeostasis, for photoreceptor cell survival.

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A Functional Binding Domain in the Rbpr2 Receptor Is Required for Vitamin A Transport, Ocular Retinoid Homeostasis, and Photoreceptor Cell Survival in Zebrafish

Cells ◽

10.3390/cells9051099 ◽

2020 ◽

Vol 9 (5) ◽

pp. 1099

Author(s):

Ashish K. Solanki ◽

Altaf A. Kondkar ◽

Joseph Fogerty ◽

Yanhui Su ◽

Seok-Hyung Kim ◽

...

Keyword(s):

Vitamin A ◽

Cell Survival ◽

Photoreceptor Cell ◽

Binding Protein ◽

Binding Domain ◽

Human Vision ◽

Retinol Binding Protein ◽

Dietary Vitamin ◽

Binding Residues ◽

Vitamin A Transport

Dietary vitamin A/all-trans retinol/ROL plays a critical role in human vision. ROL circulates bound to the plasma retinol-binding protein (RBP4) as RBP4-ROL. In the eye, the STRA6 membrane receptor binds to circulatory RBP4 and internalizes ROL. STRA6 is, however, not expressed in systemic tissues, where there is high affinity RBP4 binding and ROL uptake. We tested the hypothesis that the second retinol binding protein 4 receptor 2 (Rbpr2), which is highly expressed in systemic tissues of zebrafish and mouse, contains a functional RBP4 binding domain, critical for ROL transport. As for STRA6, modeling and docking studies confirmed three conserved RBP4 binding residues in zebrafish Rbpr2. In cell culture studies, disruption of the RBP4 binding residues on Rbpr2 almost completely abolished uptake of exogenous vitamin A. CRISPR-generated rbpr2-RBP4 domain zebrafish mutants showed microphthalmia, shorter photoreceptor outer segments, and decreased opsins, which were attributed to impaired ocular retinoid content. Injection of WT-Rbpr2 mRNA into rbpr2 mutant or all-trans retinoic acid treatment rescued the mutant eye phenotypes. In conclusion, zebrafish Rbpr2 contains a putative extracellular RBP4-ROL ligand-binding domain, critical for yolk vitamin A transport to the eye for ocular retinoid production and homeostasis, for photoreceptor cell survival.

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Influence of Supplemental, Dietary Vitamin A on Retinol-Binding Protein Concentrations in the Plasma of Preruminant Calves

Journal of Dairy Science ◽

10.3168/jds.s0022-0302(01)74519-5 ◽

2001 ◽

Vol 84 (3) ◽

pp. 641-648 ◽

Cited By ~ 3

Author(s):

B.J. Nonnecke ◽

M.P. Roberts ◽

J.D. Godkin ◽

R.L. Horst ◽

D.C. Hammell ◽

...

Keyword(s):

Vitamin A ◽

Binding Protein ◽

Retinol Binding Protein ◽

Dietary Vitamin

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The effect of vitamin A supplementation on serum retinol and retinol binding protein levels

Cancer Letters ◽

10.1016/0304-3835(85)90160-0 ◽

1985 ◽

Vol 29 (2) ◽

pp. 203-213 ◽

Cited By ~ 10

Author(s):

N.J. Wald ◽

H.S. Cuckle ◽

R.D. Barlow ◽

P. Thompson ◽

K. Nanchahal ◽

...

Keyword(s):

Vitamin A ◽

Binding Protein ◽

Retinol Binding Protein ◽

Serum Retinol ◽

Vitamin A Supplementation ◽

Protein Levels

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Relationship of holo-free and transthyretin-bound plasma retinol-binding protein levels with liver vitamin A in rats

The Journal of Nutritional Biochemistry ◽

10.1016/0955-2863(92)90065-q ◽

1992 ◽

Vol 3 (1) ◽

pp. 31-37 ◽

Cited By ~ 4

Author(s):

Betty J. Burri ◽

Mark A. Kutnink ◽

Terry R. Neidlinger

Keyword(s):

Vitamin A ◽

Binding Protein ◽

Retinol Binding Protein ◽

Protein Levels ◽

Plasma Retinol ◽

Relationship Of ◽

Liver Vitamin

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Vitamin a and its Transport Proteins in Patients with Chronic Renal Failure Receiving Maintenance Haemodialysis and after Renal Transplantation

Clinical Science ◽

10.1042/cs0650619 ◽

1983 ◽

Vol 65 (6) ◽

pp. 619-626 ◽

Cited By ~ 19

Author(s):

J. Kelleher ◽

C. S. Humphrey ◽

Dana Homer ◽

A. M. Davison ◽

G. R. Giles ◽

...

Keyword(s):

Renal Failure ◽

Renal Transplantation ◽

Chronic Renal Failure ◽

Vitamin A ◽

Binding Protein ◽

Serum Vitamin ◽

Retinol Binding Protein ◽

Maintenance Haemodialysis ◽

Protein Levels ◽

Normal Individuals

1. Serum vitamin A, retinol binding protein, prealbumin and transferrin have been studied in chronic renal failure patients receiving maintenance haemodialysis and after renal transplantation. 2. Vitamin A and retinol binding protein were uniformly raised in haemodialysis patients and this was unrelated to the period on dialysis. There was a molar excess of retinol binding protein to both vitamin A and prealbumin as compared with normal individuals. 3. Renal transplantation significantly reduces serum vitamin A and retinol binding protein concentrations but has no effect on prealbumin concentrations. The reduction in vitamin A and retinol binding protein is variable in individual patients and cannot be predicted either by the allograft function or time since transplantation. 4. Several years after transplantation, with normal serum creatinine, both serum vitamin A and retinol binding protein levels may still be greatly increased. Despite the very high vitamin A and retinol binding protein concentrations, the close correlation between the two seen in normal individuals is well maintained. 5. The continuing high vitamin A and retinol binding protein levels in patients with satisfactorily functioning transplants is unexplained.

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