Vitamin A metabolism: α-Tocopherol modulates tissue retinol levels in vivo, and retinyl palmitate hydrolysis in vitro

1984 ◽  
Vol 230 (1) ◽  
pp. 194-202 ◽  
Author(s):  
Joseph L. Napoli ◽  
Anne M. McCormick ◽  
Brian O'Meara ◽  
Edward A. Dratz
Keyword(s):  
Vitamin A ◽  
Retinyl Palmitate ◽  
Vitamin A Metabolism

scholarly journals Effect of excessive vitamin A intake on muscle protein turnover in the rat

1982 ◽  
Vol 202 (2) ◽  
pp. 499-508 ◽  
Author(s):  
F B Hillgartner ◽  
D Morin ◽  
R J Hansen
Keyword(s):  
Vitamin A ◽  
Muscle Protein ◽  
Day Treatment ◽  
Retinyl Palmitate ◽  
Protein Breakdown ◽  
Perfusion Medium ◽  
High Doses ◽  
Intact Rats

3-Methylhistidine excretion in vivo and in vitro was monitored in hypervitaminotic and pair-fed control rats. Feeding with excess of retinyl palmitate (40 000 i.u./day per 100 g body wt.) significantly increased urinary 3-methylhistidine and creatinine output during a 4-day treatment interval. 3-Methylhistidine release from perfused rat hindquarters was also elevated after 5 days of vitamin treatment. To determine whether the adrenals were involved in mediating the above response, a study was conducted on adrenalectomized and sham-operated rats. Excessive vitamin A intake stimulated 3-methylhistidine excretion in vivo and in vitro in both adrenalectomized and sham-operated animals, thus suggesting that the vitamin A-induced acceleration in myofibrillar protein breakdown was not mediated by the adrenals. In both groups of rats, vitamin A treatment had no effect on the rate of protein synthesis, on the basis of incorporation in vitro of [3H]phenylalanine into muscle protein. Additional studies revealed that the addition of excess retinol to the perfusion medium (10 i.u./ml) had no significant effect on the rates of 3-methylhistidine release or [3H]phenylalanine incorporation in vitro. Finally, high doses of cortisol (7 mg/day per 100g body wt.) administered to intact rats for 5 days significantly increased rates of 3-methylhistidine excretion, both in vivo and in vitro.

scholarly journals Cellular basis of urothelial squamous metaplasia

2005 ◽  
Vol 171 (5) ◽  
pp. 835-844 ◽  
Author(s):  
Feng-Xia Liang ◽  
Maarten C. Bosland ◽  
Hongying Huang ◽  
Rok Romih ◽  
Solange Baptiste ◽  
...  
Keyword(s):  
Vitamin A ◽  
Vitamin A Deficiency ◽  
Squamous Metaplasia ◽  
Culture Conditions ◽  
Growth Potential ◽  
Basal Cells ◽  
Cellular Basis ◽  
Proximal Urethra

Although the epithelial lining of much of the mammalian urinary tract is known simply as the urothelium, this epithelium can be divided into at least three lineages of renal pelvis/ureter, bladder/trigone, and proximal urethra based on their embryonic origin, uroplakin content, keratin expression pattern, in vitro growth potential, and propensity to keratinize during vitamin A deficiency. Moreover, these cells remain phenotypically distinct even after they have been serially passaged under identical culture conditions, thus ruling out local mesenchymal influence as the sole cause of their in vivo differences. During vitamin A deficiency, mouse urothelium form multiple keratinized foci in proximal urethra probably originating from scattered K14-positive basal cells, and the keratinized epithelium expands horizontally to replace the surrounding normal urothelium. These data suggest that the urothelium consists of multiple cell lineages, that trigone urothelium is closely related to the urothelium covering the rest of the bladder, and that lineage heterogeneity coupled with cell migration/replacement form the cellular basis for urothelial squamous metaplasia.

Vitamin A alters the internal viscosity of fragments of limb-bud mesenchyme

Development ◽  
1980 ◽  
Vol 59 (1) ◽  
pp. 325-339
Author(s):  
T. E. Kwasigroch ◽  
D. M. Kochhar
Keyword(s):  
Retinoic Acid ◽  
Vitamin A ◽  
Mesenchymal Cells ◽  
Limb Bud ◽  
Mouse Limb ◽  
Vitamin A Acid ◽  
Internal Viscosity ◽  
Fusion Experiments

Two techniques were used to examine the effect of vitamin A compounds (vitamin A acid = retinoic acid and vitamin A acetate) upon the relative strengths of adhesion among mouse limb-bud mesenchymal cells. Treatment with retinoic acid in vivo and with vitamin A acetate in vitro reduced the rate at which the fragments of mesenchyme rounded-up when cultured on a non-adhesive substratum, but these compounds did not alter the behavior of tissues tested in fragment-fusion experiments. These conflicting results indicate that the two tests measure different activities of cells and suggest that treatment with vitamin A alters the property(ies) of cells which regulate the internal viscosity of tissues.

The Effect of Vitamin A on Bone Resorptive Lesions of Periradicular Periodontitis In Vivo and In Vitro

2012 ◽  
pp. 383-386
Author(s):  
Jennifer Hong ◽  
Marcelo J. B. Silva ◽  
Mikihito Kajiya ◽  
Emad Alshwaimi ◽  
Hajime Sasaki ◽  
...  
Keyword(s):  
Vitamin A

scholarly journals Retinol and Retinyl Palmitate in Foetal Lung Mice: Sexual Dimorphism

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Olga Carvalho ◽  
Carlos Gonçalves
Keyword(s):  
Sexual Dimorphism ◽  
Vitamin A ◽  
Hplc Analysis ◽  
Prenatal Development ◽  
Retinyl Palmitate ◽  
Control Group ◽  
Male And Female ◽  
Vitamin A Metabolism ◽  
Pregnant Females ◽  
Foetal Lung

In this work, we evaluate the lung retinoids content to study the possible difference between male and female mice during prenatal development and to comprehend if the vitamin A metabolism is similar in both genders. The study occurred between developmental days E15 and E19, and the retinol and retinyl palmitate lung contents were determined by HPLC analysis. We established two main groups: the control, consisting of foetuses obtained from pregnant females without any manipulation, and vitamin A, composed of foetuses from pregnant females submitted to vitamin A administration on developmental day E14. Each of these groups was subdivided by gender, establishing the four final groups. In the lung of control group, retinol was undetected in both genders and retinyl palmitate levels exhibited a sexual dimorphism. In the vitamin A group, we detected retinol and retinyl palmitate in both genders, and we observed a more evident sexual dimorphism for both retinoids. Our study also indicates that, from developmental day E15 to E19, there is an increase in the retinoids content in foetal lung and a gender difference in the retinoids metabolism. In conclusion, there is a sexual dimorphism in the lung retinoids content and in its metabolism during mice development.

In vivo and in vitro Study of the Effects of Vitamin A Deficiency on Rat Third Molar Development

1986 ◽  
Vol 65 (12) ◽  
pp. 1445-1448 ◽  
Author(s):  
S.S. Harris ◽  
J.M. Navia
Keyword(s):  
Vitamin A ◽  
Organ Culture ◽  
Culture System ◽  
Vitamin A Deficiency ◽  
Third Molar ◽  
In Vitro Study ◽  
Organ Culture System ◽  
Vitamin A Status

We have examined the effect of in vivo vitamin A status on subsequent rat third molar formation and mineralization in an in vitro organ culture system. Vitamin A deficiency imposed during an eight-day in vitro period caused effects very similar to those of vitamin A deficiency imposed on rats in vivo. Analysis of the data also demonstrates that retinoic acid is capable of reversing the interference in mineralization of third molars induced by vitamin A deficiency in the organ culture system.

scholarly journals Utilization of retinoids in the bullfrog retina.

1982 ◽  
Vol 80 (6) ◽  
pp. 885-913 ◽  
Author(s):  
J I Perlman ◽  
B R Nodes ◽  
D R Pepperberg
Keyword(s):  
Vitamin A ◽  
Visual Pigment ◽  
Outer Segment ◽  
Rana Catesbeiana ◽  
Retinyl Palmitate ◽  
Visual Cycle ◽  
Trans Isomers ◽  
Isolated Retina ◽  
Cis Isomer

The capacity to generate 11-cis retinal from retinoids arising naturally in the eye was examined in the retina of the bullfrog, Rana catesbeiana. Retinoids, co-suspended with phosphatidylcholine, were applied topically to the photoreceptor surface of the isolated retina after substantial bleaching of the native visual pigment. The increase in photoreceptor sensitivity associated with the formation of rhodopsin, used as an assay for the appearance of 11-cis retinal in the receptors, was analyzed by extracellular measurement of the photoreceptor potential; in separate experiments using the isolated retina or receptor outer segment preparations, the formation of rhodopsin was measured spectrophotometrically. Treatments with the 11-cis isomers of retinal and retinol induced significant increases in both the rhodopsin content and photic sensitivity of previously bleached receptors. The all-trans isomers of retinyl palmitate, retinol, and retinal, as well as the 11-cis isomer of retinyl palmitate, were inactive by both the electrophysiological and spectrophotometric criteria for the generation of rhodopsin. Treatment with any one of the "inactive" retinoids did not abolish the capacity of subsequently applied 11-cis retinal or 11-cis retinol to promote the formation of rhodopsin. The data are discussed in relation to the interconversions of retinoids ("visual cycle of vitamin A") thought to mediate the regeneration of rhodopsin in vivo after extensive bleaching.

Chick Rearing III. The effect of diet on vitamin A, xanthophyll and carotene metabolism

1945 ◽  
Vol 35 (2) ◽  
pp. 101-107 ◽  
Author(s):  
T. Barton Mann
Keyword(s):  
Vitamin A ◽  
Fish Meal ◽  
Vitamin A Metabolism ◽  
Meat Meal ◽  
Basal Ration

Evidence is presented, based on feeding tests, that vitamin A metabolism is adversely affected when meat meal having a vitamin A consuming power in vitro is included in the diet of chicks.Evidence is presented, based on feeding tests, that when fish meal having no vitamin A consuming power in vitro is fed to chicks in a basal ration which produces negligible mortality, the addition of such fish meal to the ration does not appreciably increase mortality.Evidence is presented, based on feeding tests, that when fish meal having a vitamin A consuming power in vitro is fed to chicks in a basal ration which produces negligible mortality, the addition of such fish meal to the ration causes appreciable mortality.

scholarly journals In Vitro Effects of Vitamin and Mineral Supplements on Antibiotic Resistance Profile of Some ESKAPE Pathogens

2021 ◽  
pp. 37-46
Author(s):  
Osmond C. Ekwebelem ◽  
David C. Ekwe ◽  
Emmanuel A. Eze
Keyword(s):  
Vitamin A ◽  
Vitamin C ◽  
Nalidixic Acid ◽  
Resistant Bacteria ◽  
Mineral Supplements ◽  
Zones Of Inhibition ◽  
In Vitro Effects ◽  
Eskape Pathogens

Background: Antibiotics once seen as miracle drugs are now becoming inefficient in treating various bacterial diseases. This study aimed to evaluate the effects of vitamin and mineral supplements on the antibiogram profile of some of the multidrug-resistant bacteria, which the Infectious Diseases Society of America (IDSA) has dubbed ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter spp, Pseudomonas aeruginosa, and Enterobacter spp), the predominant cause of hospital-acquired infections (HAIs). Methodology: The in vitro effects were evaluated using the disc diffusion (Kirby-Bauer) technique. All test bacteria were inoculated onto Mueller-Hinton agar (MHA), supplemented with varying concentrations (2.5, 5, 10, 20, and 25 mg/ml) of vitamin (A, C, or E) and mineral (calcium or iron). Agar without supplements served as the control. The effects of vitamin and mineral supplements were determined by measuring the zones of inhibition to the nearest millimeter as compared to the control. Result: Zones of inhibition for nalidixic acid and ampicillin on P. aeruginosa significantly increased from 5mm to 32mm and 0mm to 18mm respectively, with increasing concentration of vitamin C. Similarly, nalidixic acid and ampicillin zones of inhibition on P. aeruginosa increased from 5mm to 12mm and 0mm to 18mm respectively, with increasing concentration of vitamin A. Vitamin C resulted in significant decreases in all of the zones of inhibition for all antibiotics against E. coli, except reflacine and ciproflox. Varying concentrations of iron led to a sharp decrease in the zones of inhibition for all antibiotics against S. aureus and K. pneumonia. Significant changes were also observed in all zones of inhibitions for all antibiotics studied under varying concentrations of calcium. Conclusion: The effects of vitamin and mineral supplements appear to be important but concentration-dependent. However, there is a need to evaluate the in vivo effects of these vitamin and mineral supplements.

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