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Amounts and types of fatty acids in meals affect the pattern of retinoids secreted in human chylomicrons after a high-dose preformed vitamin A intake.
Metabolism. 2003 Apr; 52(4):514-9.M

Abstract

High doses of preformed vitamin A are commonly used to correct vitamin A deficiency. Newly absorbed vitamin A is secreted mainly as retinyl esters in chylomicrons. The effect of changing types and amounts of fatty acids on fatty acid composition of chylomicron retinoid esters when a high dose of vitamin A is ingested have not been studied previously. In the present study, 10 healthy young men ingested, in a random order, mixed meals containing 15,000 retinol equivalents (RE) of vitamin A (as retinyl palmitate) and either no fat or 40 g of fat provided as butter, olive oil, or sunflower oil. Fasting and postprandial blood samples were obtained for 7 hours after meals. Free retinol and the main retinyl esters (retinyl palmitate/oleate, stearate, and linoleate) were measured in chylomicrons by high-performance liquid chromatography (HPLC). Chylomicron retinyl palmitate/oleate and retinyl stearate concentrations significantly increased after intake of the 4 test meals. Conversely, chylomicron retinyl linoleate and chylomicron free retinol significantly increased only after the sunflower and the fat-free meals, respectively. The main retinoid secreted in chylomicrons after the intake of the fat-rich meals was retinyl palmitate/oleate, accounting for 63% to 79% of total RE, but it was free retinol after the fat-free meal (51% of total RE). Thus, the retinoid pattern secreted in chylomicrons after the intake of a high dose of preformed vitamin A depends on type and amounts of fatty acids ingested. To explain this result we suggest that the esterification process of retinol in the enterocyte by lecithin:retinol acyltransferase can be overwhelmed by a high load of vitamin A. Consequently, a significant proportion of the retinol is esterified by acyl coenzyme A:retinol acyltransferase (ARAT) with ingested fatty acids, explaining the appearance of retinyl linoleate in chylomicrons after the sunflower oil meal. If a high dose of preformed vitamin A is ingested with a fat-free meal, a significant proportion of retinol is not esterified, owing to the lack of fatty acids for ARAT, which explains the appearance of free retinol in chylomicrons.

Authors+Show Affiliations

Unité Maladies Métaboliques et Micronutriments, INRA, Clermont-Ferrand/Theix, Saint-Genès-Champanelle, France.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Clinical Trial
Journal Article
Randomized Controlled Trial
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

12701068

Citation

Sauvant, Patrick, et al. "Amounts and Types of Fatty Acids in Meals Affect the Pattern of Retinoids Secreted in Human Chylomicrons After a High-dose Preformed Vitamin a Intake." Metabolism: Clinical and Experimental, vol. 52, no. 4, 2003, pp. 514-9.
Sauvant P, Mekki N, Charbonnier M, et al. Amounts and types of fatty acids in meals affect the pattern of retinoids secreted in human chylomicrons after a high-dose preformed vitamin A intake. Metab Clin Exp. 2003;52(4):514-9.
Sauvant, P., Mekki, N., Charbonnier, M., Portugal, H., Lairon, D., & Borel, P. (2003). Amounts and types of fatty acids in meals affect the pattern of retinoids secreted in human chylomicrons after a high-dose preformed vitamin A intake. Metabolism: Clinical and Experimental, 52(4), 514-9.
Sauvant P, et al. Amounts and Types of Fatty Acids in Meals Affect the Pattern of Retinoids Secreted in Human Chylomicrons After a High-dose Preformed Vitamin a Intake. Metab Clin Exp. 2003;52(4):514-9. PubMed PMID: 12701068.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Amounts and types of fatty acids in meals affect the pattern of retinoids secreted in human chylomicrons after a high-dose preformed vitamin A intake. AU - Sauvant,Patrick, AU - Mekki,Nadia, AU - Charbonnier,Monique, AU - Portugal,Henri, AU - Lairon,Denis, AU - Borel,Patrick, PY - 2003/4/18/pubmed PY - 2003/5/20/medline PY - 2003/4/18/entrez SP - 514 EP - 9 JF - Metabolism: clinical and experimental JO - Metab. Clin. Exp. VL - 52 IS - 4 N2 - High doses of preformed vitamin A are commonly used to correct vitamin A deficiency. Newly absorbed vitamin A is secreted mainly as retinyl esters in chylomicrons. The effect of changing types and amounts of fatty acids on fatty acid composition of chylomicron retinoid esters when a high dose of vitamin A is ingested have not been studied previously. In the present study, 10 healthy young men ingested, in a random order, mixed meals containing 15,000 retinol equivalents (RE) of vitamin A (as retinyl palmitate) and either no fat or 40 g of fat provided as butter, olive oil, or sunflower oil. Fasting and postprandial blood samples were obtained for 7 hours after meals. Free retinol and the main retinyl esters (retinyl palmitate/oleate, stearate, and linoleate) were measured in chylomicrons by high-performance liquid chromatography (HPLC). Chylomicron retinyl palmitate/oleate and retinyl stearate concentrations significantly increased after intake of the 4 test meals. Conversely, chylomicron retinyl linoleate and chylomicron free retinol significantly increased only after the sunflower and the fat-free meals, respectively. The main retinoid secreted in chylomicrons after the intake of the fat-rich meals was retinyl palmitate/oleate, accounting for 63% to 79% of total RE, but it was free retinol after the fat-free meal (51% of total RE). Thus, the retinoid pattern secreted in chylomicrons after the intake of a high dose of preformed vitamin A depends on type and amounts of fatty acids ingested. To explain this result we suggest that the esterification process of retinol in the enterocyte by lecithin:retinol acyltransferase can be overwhelmed by a high load of vitamin A. Consequently, a significant proportion of the retinol is esterified by acyl coenzyme A:retinol acyltransferase (ARAT) with ingested fatty acids, explaining the appearance of retinyl linoleate in chylomicrons after the sunflower oil meal. If a high dose of preformed vitamin A is ingested with a fat-free meal, a significant proportion of retinol is not esterified, owing to the lack of fatty acids for ARAT, which explains the appearance of free retinol in chylomicrons. SN - 0026-0495 UR - https://www.unboundmedicine.com/medline/citation/12701068/Amounts_and_types_of_fatty_acids_in_meals_affect_the_pattern_of_retinoids_secreted_in_human_chylomicrons_after_a_high_dose_preformed_vitamin_A_intake_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0026049502052915 DB - PRIME DP - Unbound Medicine ER -