Fate of orally administered radioactive fatty acids in the late-pregnant rat

To investigate the biodisponibility of placental transfer of fatty acids, rats pregnant for 20 days were given tracer amounts of [14C]palmitic (PA), oleic (OA), linoleic (LA), α-linolenic (LNA), or docosahexaenoic acid (DHA) orally and euthanized at 0.5, 1.0, 2.0, or 8.0 h thereafter. Maternal plasma radioactivity in lipids initially increased only to decline at later times. Most of the label appeared first as triacylglycerols (TAG); later, the proportion in phospholipids (PhL) increased. The percentage of label in placental lipids was also always highest shortly after administration and declined later; again, PhL increased with time. Fetal plasma radioactivity increased with time, with its highest value at 8.0 h after DHA or LNA administration. DHA initially appeared primarily in the nonesterified fatty acids (NEFA) and PA, OA, LA, and LNA as TAG followed by NEFA; in all cases, there was an increase in PhL at later times. Measurement of fatty acid concentrations allowed calculation of specific (radio)activities, and the ratio (fetal/maternal) of these in the plasmas gave an index of placental transfer activity, which was LNA > LA > DHA = OA > PA. It is proposed that a considerable proportion of most fatty acids transferred through the placenta are released into the fetal circulation in the form of TAG.

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Placental transfer of I131-insulin in the rhesus monkey

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1961.200.3.471 ◽

1961 ◽

Vol 200 (3) ◽

pp. 471-476 ◽

Cited By ~ 20

Author(s):

J. B. Josimovich ◽

E. Knobil

Keyword(s):

Placental Transfer ◽

Degradation Products ◽

Venous Blood ◽

Maternal Blood ◽

Maternal Plasma ◽

Maternal Circulation ◽

Fetal Circulation ◽

Fetal Plasma ◽

Arterial Blood ◽

Venous Plasma

Pregnant rhesus monkeys were anesthetized, their uteri were exposed, and the interplacental vessels (fetal circulation) were cannulated without incision of the amnion. This procedure permitted simultaneous sampling of maternal blood, umbilical venous blood and umbilical arterial blood. I131-labeled insulin injected into the material circulation was detected in umbilical venous plasma, within 5 minutes after the injection, by the use of a chromatographic procedure which permits the separation of I131-insulin from other iodinated compounds. The concentration of I131-insulin in fetal plasma did not exceed 20% of that found concurrently in maternal plasma. A marked umbilical arterial-venous difference in I131-insulin concentration was consistently observed. The concentration of iodinated degradation products of I131-insulin was considerably higher in umbilical arterial plasma than in umbilical venous plasma, suggesting rapid degradation of the labeled hormone by the fetus. Conversely, the injection of I131-insulin into the fetal circulation was followed by the appearance of significant quantities of the labeled hormone in the maternal circulation. These experiments lead to the conclusion that insulin can cross the primate placenta.

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Seasonal Variation in Plasma Nonesterified Fatty Acids of Lake Sturgeon (Acipenser fulvescens) in the Vicinity of Hydroelectric Facilities

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f93-268 ◽

1993 ◽

Vol 50 (11) ◽

pp. 2440-2447 ◽

Cited By ~ 15

Author(s):

R. S. McKinley ◽

T. D. Singer ◽

J. S. Ballantyne ◽

G. Power

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Lake Sturgeon ◽

Acipenser Fulvescens ◽

Total Plasma ◽

Nefa Concentration ◽

Plasma Nefa ◽

Nonesterified Fatty Acids ◽

Plasma Nefa Concentration ◽

Fatty Acid Species

To establish the effects of hydroelectric generation on the health of lake sturgeon (Acipenser fulvescens), seasonal variations in plasma nonesterified fatty acids (NEFAs) upstream and downstream from hydroelectric stations were measured over a 2-yr period. Plasma NEFA profiles were also compared up- and downstream of the stations for differences in utilization of individual NEFA species as substrates for lipid oxidation. Significantly higher levels of total plasma NEFA were found in lake sturgeon upstream (2355 ± 395.9 nmol/mL) compared with those downstream (798 ± 133.5 nmol/mL) of the generating stations during the spring. The NEFA profiles for several key fatty acid species differed significantly among seasons up- and downstream of the facilities. In particular, during spring and summer, the levels of oleic acid (18:1n9) were highest upstream of the stations and levels of a polyunsaturated fatty acid, docosahexaenoic acid (22:6n3), were higher below rather than above the stations. The differences in plasma NEFA concentration may be attributed to altered nutritional status due to the varying flow regime located downstream of the hydroelectric stations.

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Placental Transfer of Free Fatty Acids in the Pregnant Rat

Experimental Biology and Medicine ◽

10.3181/00379727-116-29263 ◽

1964 ◽

Vol 116 (2) ◽

pp. 411-414 ◽

Cited By ~ 35

Author(s):

Z. Koren ◽

E. Shafrir

Keyword(s):

Fatty Acids ◽

Free Fatty Acids ◽

Placental Transfer ◽

Pregnant Rat

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Thyroid and parathyroid-independent increase in plasma 1,25-dihydroxyvitamin D during late pregnancy in the rat

Journal of Endocrinology ◽

10.1677/joe.0.1160381 ◽

1988 ◽

Vol 116 (3) ◽

pp. 381-385 ◽

Cited By ~ 9

Author(s):

T. M. Nguyen ◽

A. Halhali ◽

H. Guillozo ◽

M. Garabedian ◽

S. Balsan

Keyword(s):

Vitamin D ◽

Placental Transfer ◽

Plasma Concentrations ◽

Late Pregnancy ◽

Maternal Plasma ◽

Vitamin D Metabolites ◽

Pregnant Rats ◽

Dihydroxyvitamin D ◽

Fetal Plasma ◽

And Control

ABSTRACT The effect of thyroparathyroidectomy (TPTX) on the plasma concentrations of the vitamin D metabolites (25-(OH)D, 24,25-(OH)2D and 1,25-(OH)2D) has been studied in pregnant rats and their fetuses during the last quarter of gestation. Maternal and fetal vitamin D metabolites were not significantly affected by TPTX. A significant increase in plasma 1,25-(OH)2D concentrations was observed in both TPTX and control mothers and fetuses from days 19 to 21. Fetal and maternal plasma 25-(OH)D were positively correlated in both control and TPTX groups. Such a correlation was also found for 24,25-(OH)2D in the two groups. In contrast, a positive correlation between maternal and fetal plasma concentrations of 1,25-(OH)2D was found in TPTX but not in control rats. These data suggest that major alterations in calcium metabolism, such as that produced by maternal TPTX, are insufficient to affect the changes in maternal and fetal plasma 1,25-(OH)2D during late pregnancy significantly. They also suggest that parathyroid hormone, thyroxine, and/or calcitonin may control a possible placental transfer of 1,25-(OH)2D in the rat. J. Endocr. (1988) 116, 381–385

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Carnitine in the Perinatal Metabolism of Lipids I. Relationship Between Maternal and Fetal Plasma Levels of Carnitine and Acylcarnitines

PEDIATRICS ◽

10.1542/peds.67.1.95 ◽

1981 ◽

Vol 67 (1) ◽

pp. 95-100

Author(s):

Milan Novak ◽

Ellen F. Monkus ◽

Dina Chung ◽

Maria Buch

Keyword(s):

Fatty Acid ◽

Fatty Acid Oxidation ◽

Plasma Levels ◽

Umbilical Vein ◽

Maternal Plasma ◽

Free Carnitine ◽

Acid Oxidation ◽

Limited Capacity ◽

Fetal Plasma ◽

Arterial Plasma

Since premature infants have a limited capacity for fatty acid oxidation, supplementation with carnitine may improve their utilization of fat. Documentation of the source and extent of fetal carnitine reserves should explain the possible need for exogenous carnitine in the neonate. Correlation between free carnitine concentration in maternal and umbilical arterial plasma at birth (r = .45, P < .01) indicates that the initial concentration of free carnitine in the newborn depends on the maternal level. Thin-layer chromatography shows more γ-butyrobetaine in maternal than umbilical arterial plasma indicating higher availability of the precursor of carnitine biosynthesis. Elevated fatty acid oxidation in maternal tissues seems to be reflected by larger amounts of long-chain acylcarnitines in maternal plasma. Shortchain acylcarnitines, mainly acetylcarnitine, are higher in the umbilical vein than in maternal plasma (P < .01) indicating that the conceptus (the placenta or fetus) is either producing more or utilizing less acetylcarnitine. Plasma levels of carnitine rapidly decrease in premature newborns during the first three days after birth if no exogenous carnitine is given (P < .001), while no significant changes of total carnitine were detected in adult patients on total parenteral alimentation for one week. This difference indicates lower carnitine depots or limited capacity for carnitine biosynthesis in neonates. The possibility still requires further investigation that the development of the optimal rate of fatty acid oxidation in human newborns, as well as in other newborn mammals, may depend on the supply of exogenous carnitine.

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Intramuscular fatty acid metabolism evaluated with stable isotopic tracers

Journal of Applied Physiology ◽

10.1152/jappl.1998.84.5.1674 ◽

1998 ◽

Vol 84 (5) ◽

pp. 1674-1679 ◽

Cited By ~ 45

Author(s):

Zengkui Guo ◽

Michael D. Jensen

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Fatty Acid Metabolism ◽

Acid Metabolism ◽

Isotope Ratio Mass Spectrometry ◽

Isotopic Tracers ◽

Nonesterified Fatty Acids ◽

Stable Isotopic ◽

Fractional Synthesis ◽

Intramuscular Triglyceride

We evaluated the applicability of stable isotopic tracers to the study of intramuscular fatty acid metabolism by infusing both [U-13C]palmitate and [1-13C]oleate intravenously for 4 h into fasted conscious rats. Skeletal muscles were sequentially biopsied, and the concentration and13C enrichment of fatty acids were measured by gas chromatography/combustion/isotope ratio mass spectrometry. Throughout the study, the13C enrichment of plasma palmitate and oleate remained substantially greater than intramuscular nonesterified palmitate and oleate enrichment, which in turn was greater than intramuscular triglyceride palmitate and oleate enrichment. Fractional synthesis rates of intramuscular triglycerides in gastrocnemius and soleus were 0.267 ± 0.075 and 0.100 ± 0.030/h ( P = 0.04), respectively, as determined by using [U-13C]palmitate, and were 0.278 ± 0.049 and 0.075 ± 0.013/h ( P = 0.02), respectively, by using [1-13C]oleate. We conclude that plasma free fatty acids are a source for intramuscular triglycerides and nonesterified fatty acids; the latter are likely the synthetic precursors of the former. Uniformly and singly labeled [13C]fatty acid tracers will provide an important tool to study intramuscular fatty acid and triglyceride metabolism.

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Improved energy homeostasis of the heart in the metabolic state of exercise

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.2000.279.4.h1490 ◽

2000 ◽

Vol 279 (4) ◽

pp. H1490-H1501 ◽

Cited By ~ 73

Author(s):

Gary W. Goodwin ◽

Heinrich Taegtmeyer ◽

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Fatty Acid Oxidation ◽

Energy Homeostasis ◽

Acid Oxidation ◽

High Fat ◽

Nonesterified Fatty Acids ◽

Malonyl Coa ◽

Metabolic Conditions ◽

High Lactate

We postulate that metabolic conditions that develop systemically during exercise (high blood lactate and high nonesterified fatty acids) are favorable for energy homeostasis of the heart during contractile stimulation. We used working rat hearts perfused at physiological workload and levels of the major energy substrates and compared the metabolic and contractile responses to an acute low-to-high work transition under resting versus exercising systemic metabolic conditions (low vs. high lactate and nonesterified fatty acids in the perfusate). Glycogen preservation, resulting from better maintenance of high-energy phosphates, was a consequence of improved energy homeostasis with high fat and lactate. We explained the result by tighter coupling between workload and total β-oxidation. Total fatty acid oxidation with high fat and lactate reflected increased availability of exogenous and endogenous fats for respiration, as evidenced by increased long-chain fatty acyl-CoA esters (LCFA-CoAs) and by an increased contribution of triglycerides to total β-oxidation. Triglyceride turnover (synthesis and degradation) also appeared to increase. Elevated LCFA-CoAs caused high total β-oxidation despite increased malonyl-CoA. The resulting bottleneck at mitochondrial uptake of LCFA-CoAs stimulated triglyceride synthesis. Our results suggest the following. First, both malonyl-CoA and LCFA-CoAs determine total fatty acid oxidation in heart. Second, concomitant stimulation of peripheral glycolysis and lipolysis should improve cardiac energy homeostasis during exercise. We speculate that high lactate contributes to the salutary effect by bypassing the glycolytic block imposed by fatty acids, acting as an anaplerotic substrate necessary for high tricarbocylic acid cycle flux from fatty acid-derived acetyl-CoA.

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Omega-3 fatty acids transport through the placenta

Asian Journal of Medical and Biological Research ◽

10.3329/ajmbr.v2i1.27561 ◽

2016 ◽

Vol 2 (1) ◽

pp. 1-8

Author(s):

Ariful Islam ◽

Takanori Kodama ◽

Yui Yamamoto ◽

Majid Ebrahimi ◽

Hirofumi Miyazaki ◽

...

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Placental Transfer ◽

Fatty Acid Binding Proteins ◽

Fatty Acid Transport ◽

Omega 3 ◽

Fatty Acid Binding ◽

Membrane Bound ◽

Fatty Acid Transport Proteins

The placenta is a temporary vital organ for sustaining the development of the fetus throughout gestation. Although the fatty acid composition delivered to the fetus is largely determined by maternal circulating levels, the placenta preferentially transfers physiologically important long-chain polyunsaturated fatty acids (LC-PUFAs), particularly omega-3 (n-3) FAs. The precise mechanisms governing these transfers were covered in a veil, but have started to be revealed gradually. Several evidences suggest fatty acid transport proteins (FATPs), placental specific membrane bound fatty acid binding proteins (pFABPpm) and fatty acid translocases (FAT/CD36) involved in LC-PUFAs uptake. Our studies have shown that the placental transfer of omega-3 FAs through the trophoblast cells is largely contributed by fatty acid binding protein 3 (FABP3). Recently there are considerable interests in the potential for dietary omega-3 FAs as a therapeutic intervention for fetal disorders. In fact, prenatal supply of omega-3 FAs is essential for brain and retinal development. Recent findings suggest a potential opportunity of omega-3 FA interventions to decrease the incidence of type 2 diabetes in future generations. In this review, we discuss the molecular mechanism of transportation of omega-3 FAs through the placenta and how omega-3 FAs deficiency/supplementation impact on fetal development.Asian J. Med. Biol. Res. March 2016, 2(1): 1-8

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1,25(OH)2D3 and Ca-binding protein in fetal rats: relationship to the maternal vitamin D status

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1988.254.4.e505 ◽

1988 ◽

Vol 254 (4) ◽

pp. E505-E512 ◽

Cited By ~ 5

Author(s):

J. Verhaeghe ◽

M. Thomasset ◽

A. Brehier ◽

F. A. Van Assche ◽

R. Bouillon

Keyword(s):

Vitamin D ◽

Calcium Binding ◽

Maternal Plasma ◽

Diabetic Rats ◽

Pregnant Rats ◽

Pregnant Rat ◽

Fetal Plasma ◽

Hormonal Function ◽

Low Calcium ◽

Calcium Phosphorus

The autonomy and functional role of fetal 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] were investigated in nondiabetic and diabetic BB rats fed diets containing 0.85% calcium-0.7% phosphorus or 0.2% calcium and phosphorus and in semistarved rats on the low calcium-phosphorus diet. The changes in maternal and fetal plasma 1,25(OH)2D3 were similar: the levels were increased by calcium-phosphorus restriction and decreased by diabetes and semistarvation. Maternal and fetal 1,25(OH)2D3 levels were correlated (r = 0.80; P less than 0.001). The vitamin D-dependent calcium-binding proteins (CaBP9K and CaBP28K) were measured in multiple maternal and fetal tissues and in the placenta of nondiabetic, diabetic, and calcium-phosphorus-restricted rats. The distributions of CaBP9K and CaBP28K in the pregnant rat were similar to that of the growing rat. The increased maternal plasma 1,25(OH)2D3 levels in calcium-phosphorus-restricted rats were associated with higher duodenal CaBP9K and renal CaBPs, but placental CaBP9K was not different. In diabetic pregnant rats, duodenal CaBP9K tended to be lower, while renal CaBPs were normal; placental CaBP9K was decreased. No significant changes in CaBP levels were observed in fetuses of low calcium-phosphorus diet rats or fetuses of diabetic rats. The results indicate that in the rat fetal 1,25(OH)2D3 depends on maternal 1,25(OH)2D3 or on factors regulating maternal 1,25(OH)2D3. The lack of changes in fetal CaBP in the presence of altered fetal plasma 1,25(OH)2D3 levels confirms earlier data showing that 1,25(OH)2D3 has a limited hormonal function during perinatal development in the rat.

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