Natural Vitamin E Supplementation during Pregnancy in Rats Increases RRR-α-Tocopherol Stereoisomer Proportion and Enhances Fetal Antioxidant Capacity, Compared to Synthetic Vitamin E Administration.

INTRODUCTION: Low dietary intake of vitamin E is a global public health issue. RRR-α-tocopherol (RRR-αT) is the only naturally occurring vitamin E stereoisomer, but the equimolecular mixture of all eight stereoisomers, synthetic vitamin E (S-αT), is commonly consumed. The objective of this study was to evaluate bioavailability and antioxidant activity of RRR-αT versus S-αT, in both mother and fetus, after maternal supplementation during pregnancy. METHODS: Female rats (7 weeks of age) received a modified AIN-93G diet supplemented with 75 IU/kg of RRR-αT (NVE, n = 20) or S-αT (SVE, n = 17). At delivery, the levels of αT, stereoisomer distribution, and antioxidant capacity were analyzed in maternal and fetal plasma. RESULTS: NVE administration significantly increased the proportion of RRR-αT stereoisomer in maternal and fetal plasma. The percentage of RRR-αT increased from 32.76% to 88.33% in maternal plasma, and 35.25% to 97.94% in fetal plasma, in the NVE group compared to SVE. Fetal plasma from the NVE group was found to have higher total antioxidant capacity compared to SVE. Lastly, fetal plasma RRR-αT stereoisomer percentage was positively associated with expression levels of scavenger receptor class B type 1 (SR-B1) in the placenta. CONCLUSIONS: Both natural and synthetic sources of vitamin E showed similar bioavailability. Still, NVE supplementation increased the proportion of RRR-αT and promoted higher antioxidant activity in fetal plasma at birth. Placental SR-B1 might be involved in the stereoselective transfer of RRR-αT stereoisomer across the placenta and may improve αT bioactivity in the fetus.

Carotenoids improve the development of cerebral cortical networks in formula-fed infant macaques.

Nutrition during the first years of life has a significant impact on brain development. This study characterized differences in brain maturation from birth to 6 months of life in infant macaques fed formulas differing in content of lutein, ß-carotene, and other carotenoids using Magnetic Resonance Imaging to measure functional connectivity. We observed differences in functional connectivity based on the interaction of diet, age and brain networks. Post hoc analysis revealed significant diet-specific differences between insular-opercular and somatomotor networks at 2 months of age, dorsal attention and somatomotor at 4 months of age, and within somatomotor and between somatomotor-visual and auditory-dorsal attention networks at 6 months of age. Overall, we found a larger divergence in connectivity from the breastfeeding group in infant macaques fed formula containing no supplemental carotenoids in comparison to those fed formula supplemented with carotenoids. These findings suggest that carotenoid formula supplementation influences functional brain development.

α-Tocopherol Stereoisomer Profiles in Matched Human Maternal and Umbilical Cord Plasma.

BACKGROUND: α-Tocopherol (αT) is essential for fetal development. One study has shown that the human placenta preferentially transfers the natural stereoisomer, RRR-αT. But prenatal supplements generally contain synthetic αT (S-αT). OBJECTIVES: We aimed to determine if umbilical cord plasma is enriched for RRR-αT in racially diverse neonates from both uncomplicated and complicated pregnancies and if cord RRR-αT enrichment is impacted by maternal αT stereoisomer profile. METHODS: We measured αT and αT stereoisomers in plasma from a randomly selected subset of 66 predominantly black and Hispanic maternal-fetal pairs from the Camden Study involving control (n = 28) and complicated pregnancies (n = 38). We collected maternal plasma at study entry (week 16 gestation; w16) and week 28 gestation (w28) and cord plasma at birth. RESULTS: RRR-αT was the predominant stereoisomer in all maternal and cord plasma samples, but S-αT stereoisomers were found in most samples and comprised a high percentage of αT in some maternal-neonate pairs. Cord plasma had a higher percentage RRR-αT (P < 0.05) and lower percentage S-αT (P < 0.0001) than w28 plasma. Pregnancy status did not impact maternal or cord plasma concentrations of αT, RRR-αT, or S-αT; except plasma from complicated pregnancies was higher in S-αT at w28 than at w16 (P < 0.05). Maternal w28 αT did not correlate with cord αT. However, both maternal w28 αT and S-αT positively correlated with both cord S-αT (r = 0.340, P = 0.0049; r = 0.538, P < 0.00001) and percentage S-αT (r = 0.399, P = 0.001; r = 0.786, P < 0.00001) but negatively correlated with cord percentage RRR-αT (r = -0.399, P = 0.0009; r = -0.786, P < 0.00001). CONCLUSIONS: The proportion of RRR-αT was higher in cord compared with maternal plasma in both uncomplicated and complicated pregnancies. Our data suggest that maternal S-αT raises cord S-αT and decreases the proportion of RRR-αT in the neonatal circulation. Because the bioactivities of RRR-αT and S-αT differ, this warrants future research to determine the importance of our observations to neonatal αT status.

Natural and Synthetic α-Tocopherol Modulate the Neuroinflammatory Response in the Spinal Cord of Adult Ttpa-null Mice.

BACKGROUND: Vitamin E (α-tocopherol, α-T) deficiency causes neurological pathologies. α-T supplementation improves outcomes, but the relative bioactivities of dietary natural and synthetic α-T in neural tissues are unknown. OBJECTIVE: The aim was to assess the effects of dietary α-T source and dose on oxidative stress and myelination in adult α-tocopherol transfer protein-null (Ttpa- / - ) mouse cerebellum and spinal cord. METHODS: Three-week-old male Ttpa- / - mice (n = 56) were fed 1 of 4 AIN-93G-based diets for 37 wk: vitamin E-deficient (VED; below α-T limit of detection); natural α-T, 600 mg/kg diet (NAT); synthetic α-T, 816 mg/kg diet (SYN); or high synthetic α-T, 1200 mg/kg diet (HSYN). Male Ttpa+/+ littermates (n = 14) fed AIN-93G (75 mg synthetic α-T/kg diet; CON) served as controls. At 40 wk of age, total and stereoisomer α-T concentrations and oxidative stress markers were determined (n = 7/group). Cerebellar Purkinje neuron morphology and white matter areas in cerebellum and spinal cord were assessed in a second subset of animals (n = 7/group). RESULTS: Cerebral cortex α-T concentrations were undetectable in Ttpa- / - mice fed the VED diet. α-T concentrations were increased in NAT (4.6 ± 0.3 nmol/g), SYN (8.0 ± 0.7 nmol/g), and HSYN (8.5 ± 0.3 nmol/g) mice, but were significantly lower than in Ttpa+/+ mice fed CON (27.8 ± 1.9 nmol/g) (P < 0.001). 2R stereoisomers constituted the majority of α-T in brains of Ttpa+/+ mice (91%) and Ttpa- / - mice fed NAT (100%), but were substantially lower in the SYN and HSYN groups (∼53%). Neuroinflammatory genes were increased in the spinal cord, but not cerebellum, of VED-fed animals; NAT, SYN, and HSYN normalized their expression. Cerebellar Purkinje neuron atrophy and myelin pathologies were not visible in Ttpa- / - mice. CONCLUSIONS: Natural and synthetic α-T supplementation normalized neuroinflammatory markers in neural tissues of 10-mo-old Ttpa- / - mice. α-T prevents tissue-specific molecular abnormalities, which may prevent severe morphological changes during late adulthood.

Enhanced physical and cognitive performance in active duty Airmen: evidence from a randomized multimodal physical fitness and nutritional intervention.

Achieving military mission objectives requires high levels of performance from Airmen who operate under extreme physical and cognitive demands. Thus, there is a critical need to establish scientific interventions to enhance physical fitness and cognitive performance-promoting the resilience of Airmen and aiding in mission success. We therefore conducted a comprehensive, 12-week randomized controlled trial in active-duty Air Force Airmen (n = 148) to compare the efficacy of a multimodal intervention comprised of high-intensity interval aerobic fitness and strength training paired with a novel nutritional supplement [comprised of ß-hydroxy ß-methylbutyrate (HMB), lutein, phospholipids, DHA and selected micronutrients including B12 and folic acid] to high-intensity interval aerobic fitness and strength training paired with a standard of care placebo beverage. The exercise intervention alone improved several dimensions of physical fitness [strength and endurance (+ 8.3%), power (+ 0.85%), mobility and stability (+ 22%), heart rate (- 1.1%) and lean muscle mass (+ 1.4%)] and cognitive function [(episodic memory (+ 9.5%), processing efficiency (+ 7.5%), executive function reaction time (- 4.8%) and fluid intelligence accuracy (+ 19.5%)]. Relative to exercise training alone, the multimodal fitness and nutritional intervention further improved working memory (+ 9.0%), fluid intelligence reaction time (- 7.7%), processing efficiency (+ 1.8%), heart rate (- 2.4%) and lean muscle mass (+ 1.5%). These findings establish the efficacy of a multimodal intervention that incorporates aerobic fitness and strength training with a novel nutritional supplement to enhance military performance objectives and to provide optimal exercise training and nutritional support for the modern warfighter.

Synthetic α-Tocopherol, Compared with Natural α-Tocopherol, Downregulates Myelin Genes in Cerebella of Adolescent Ttpa-null Mice.

BACKGROUND: Vitamin E (α-tocopherol; α-T) deficiency causes spinocerebellar ataxia. α-T supplementation improves neurological symptoms, but little is known about the differential bioactivities of natural versus synthetic α-T during early life. OBJECTIVE: We assessed the effects of dietary α-T dose and source on tissue α-T accumulation and gene expression in adolescent α-tocopherol transfer protein-null (Ttpa-/-) mice. METHODS: Three-week-old male Ttpa-/- mice (n  = 7/group) were fed 1 of 4 AIN-93G-based diets for 4 wk: vitamin E deficient (VED; below α-T limit of detection); natural α-T, 600 mg/kg diet (NAT); synthetic α-T, 816 mg/kg diet (SYN); or high synthetic α-T, 1200 mg/kg diet (HSYN). Male Ttpa+/+ littermates fed AIN-93G [75 mg synthetic α-T (CON)] served as controls (n  = 7). At 7 wk of age, tissue α-T concentrations and stereoisomer profiles were measured for all groups. RNA-sequencing was performed on cerebella of Ttpa-/- groups. RESULTS: Ttpa-/- mice fed VED had undetectable brain α-T concentrations. Cerebral cortex α-T concentrations were greater in Ttpa-/- mice fed NAT (9.1 ± 0.7 nmol/g), SYN (10.8 ± 1.0 nmol/g), and HSYN (13.9 ± 1.6 nmol/g) compared with the VED group but were significantly lower than in Ttpa+/+ mice fed CON (24.6 ± 1.2 nmol/g) (P < 0.001). RRR-α-T was the predominant stereoisomer in brains of Ttpa+/+ mice (∼40%) and Ttpa-/- mice fed NAT (∼94%). α-T stereoisomer composition was similar in brains of Ttpa-/- mice fed SYN and HSYN (2R: ∼53%; 2S: ∼47%). Very few of the 16,774 genes measured were differentially expressed. However, compared with the NAT diet, HSYN significantly downregulated 20 myelin genes, including 2 transcription factors: SRY-box transcription factor 10 (Sox10) and myelin regulatory factor (Myrf), and several downstream target genes (false discovery rate <0.05). CONCLUSIONS: High-dose synthetic α-T compared with natural α-T alters myelin gene expression in the adolescent mouse cerebellum, which could lead to morphological and functional abnormalities later in life.

The effects of breastfeeding versus formula-feeding on cerebral cortex maturation in infant rhesus macaques.

Breastfeeding is positively associated with several outcomes reflecting early brain development and cognitive functioning. Brain neuroimaging studies have shown that exclusively breastfed children have increased white matter and subcortical gray matter volume compared to formula-fed children. However, it is difficult to disentangle the effects of nutrition in breast milk from other confounding factors that affect brain development, particularly in studies of human subjects. Among the nutrients provided by human breast milk are the carotenoid lutein and the natural form of tocopherol, both of which are selectively deposited in brain. Lutein is the predominant carotenoid in breast milk but not in most infant formulas, whereas infant formulas are supplemented with the synthetic form of tocopherol. In this study, a non-human primate model was used to investigate the effects of breastfeeding versus formula-feeding, as well as lutein and natural RRR-α-tocopherol supplementation of infant formula, on brain maturation under controlled experimental conditions. Infant rhesus macaques (Macaca mulatta) were exclusively breastfed, or were fed infant formulas with different levels and sources of lutein and α-tocopherol. Of note, the breastfed group were mother-reared whereas the formula-fed infants were nursery-reared. Brain structural and diffusion MR images were collected, and brain T2 was measured, at two, four and six months of age. The mother-reared breastfed group was observed to differ from the formula-fed groups by possessing higher diffusion fractional anisotropy (FA) in the corpus callosum, and lower FA in the cerebral cortex at four and six months of age. Cortical regions exhibiting the largest differences include primary motor, premotor, lateral prefrontal, and inferior temporal cortices. No differences were found between the formula groups. Although this study did not identify a nutritional component of breast milk that could be provided to infant formula to facilitate brain maturation consistent with that observed in breastfed animals, our findings indicate that breastfeeding promoted maturation of the corpus callosum and cerebral cortical gray matter in the absence of several confounding factors that affect studies in human infants. However, differences in rearing experience remain as a potential contributor to brain structural differences between breastfed and formula fed infants.

Milk and Plasma Lutein and Zeaxanthin Concentrations in Chinese Breast-Feeding Mother-Infant Dyads With Healthy Maternal Fruit and Vegetable Intake.

OBJECTIVES: While others have reported that milk from coastal Chinese women contains high levels of lutein and zeaxanthin, no research has determined the corresponding infant plasma response. Whether infant plasma levels increase commensurately provides important guidance for supplementation of these increasingly intriguing carotenoids in breast-feeding mothers and formula-fed infants. METHODS: Fifty-six mother-infant pairs with a maternal diet rich in eggs, green leafy vegetables, and fruit were enrolled between 6 and 16 weeks of lactation. Milk samples and blood samples from both the mother and infant were collected at entry. Maternal 3-day dietary records and a second milk sample were collected 1 to 3 weeks later. RESULTS: Mean milk lutein concentrations in samples 1 and 2 were 6.5 and 7.7 µg/dL (range 1-22.5 µg/dL), and for zeaxanthin, 1.6 and 1.7 µg/dL (range 1-5.9 µg/dL). Lutein concentrations in infant plasma (18.2 µg/dL) were similar to those in maternal plasma (21.6 µg/dL); zeaxanthin was lower than lutein in both maternal (3.1 µg/dL) and infant (2.9 µg/dL) plasma. Infant and maternal mean plasma lutein and zeaxanthin concentrations were higher than those in both milk samples 1 and 2 (lutein, 6.9 and 8.2 µg/dL; zeaxanthin, 1.9 and 2.0 µg/dL). Infant plasma lutein and zeaxanthin concentrations positively correlated with those in milk sample 1 (lutein, r2 = 0.15, p = 0.004; zeaxanthin, r2 = 0.21, p < 0.001). CONCLUSIONS: Together, these results reveal that high milk concentrations of lutein and zeaxanthin driven by healthy maternal intakes of xanthophyll rich foods are associated with high infant plasma concentrations. These findings will be useful for determining appropriate lutein fortification strategies. Clinical Study.gov registration number: NCT01669655.

RRR-α-Tocopherol Is the Predominant Stereoisomer of α-Tocopherol in Human Milk.

BACKGROUND: The naturally occurring α-tocopherol (α-T) stereoisomer, RRR-α-tocopherol (RRR-α-T), is known to be more bioactive than all-rac-α-tocopherol (all-rac-α-T), a synthetic racemic mixture of 8 stereoisomers. There is widespread use of all-rac-α-T in maternal supplements. OBJECTIVE: The aim of the study was to thoroughly describe the α-T stereoisomer profile of human milk. METHODS: We measured the α-T stereoisomer profile in milk from 2 cohorts of women: a cohort of 121 women who provided milk on days 30 and 60 of lactation (study 1) and a separate cohort of 51 women who provided milk on days 10, 21, 71, and 120 of lactation (study 2). RESULTS: RRR-α-T was the predominant stereoisomer (P < 0.0001) in all samples in both studies despite a large intrasubject range in total α-T (0.7-22 µg/mL). On average, RRR-α-T comprised 73-76% of total α-T, but average values for the synthetic stereoisomers were RRS, 8-14%; RSR, 6-8%; RSS, 5-6%; and the sum of 2S stereoisomers (Σ2S), 3-5%. Despite the predominance of RRR-α-T, the sum of the synthetic stereoisomers comprised as much as 48% of total α-T. We calculated the ratio of RRR to the sum of the synthetic 2R (RRS + RSR + RSS) stereoisomers (s2R) to assess the degree to which RRR is favored in milk. Consistent with discrimination among 2R stereoisomers in mammary tissue, RRR/s2R values ranged from 2.8 to 3.6, as opposed to the expected ratio of 0.33 if there was no discrimination. However, the RRR to s2R ratio did not correlate with milk α-T concentration, but both components of the ratio did. CONCLUSIONS: RRR-α-T is the predominant stereoisomer in human milk, concentrations of synthetic 2R stereoisomers were notable, and the relation between milk total α-T and stereoisomer profile is complex. Due to the wide range found in milk α-T stereoisomer profile, investigation into its impact on α-T status and functional outcomes in breastfed infants is warranted.

Relationships of carotenoid-related gene expression and serum cholesterol and lipoprotein levels to retina and brain lutein deposition in infant rhesus macaques following 6 months of breastfeeding or formula feeding.

The purpose of this study was to investigate if the enhanced bioaccumulation of lutein in retina and brain of breastfed, compared to formula-fed, infant monkeys was associated with higher levels of serum total and HDL cholesterol, apolipoproteins, or mRNA/protein expression of carotenoid-related genes. Newborn rhesus macaques were either breastfed, fed a carotenoid-supplemented formula, or fed an unsupplemented formula for 6 months (n = 8, 8, 7). Real-time qPCR and western blotting were performed in two brain regions (occipital cortex and cerebellum) and two retina regions (macular and peripheral retina). Breastfed infants had higher serum total cholesterol, HDL cholesterol, apoA-I, and apoB-100 levels than the combined formula-fed groups (P < 0.05). Breast milk or infant formulas did not alter expression of the nine genes (CD36, SCARB1, SCARB2, LDLR, STARD3, GSTP1, BCO1, BCO2, RPE65) examined except for SCARB2 in the retina and brain regions. In conclusion, dietary regimen did not impact the expression of carotenoid-related genes except for SCARB2. However, carotenoid-related genes were differentially expressed across brain and retina regions. Breastfed infants had higher serum total and HDL cholesterol, and apolipoproteins, suggesting that lipoprotein levels might be important for delivering lutein to tissues, especially the macular retina, during infancy.

Lutein Is Differentially Deposited across Brain Regions following Formula or Breast Feeding of Infant Rhesus Macaques.

Background: Lutein, a yellow xanthophyll, selectively accumulates in primate retina and brain. Lutein may play a critical role in neural and retinal development, but few studies have investigated the impact of dietary source on its bioaccumulation in infants. Objective: We explored the bioaccumulation of lutein in infant rhesus macaques following breastfeeding or formula-feeding. Methods: From birth to 6 mo of age, male and female rhesus macaques (Macaca mulatta) were either breastfed (BF) (n = 8), fed a formula supplemented with lutein, zeaxanthin, ß-carotene, and lycopene (237, 19.0, 74.2, and 338 nmol/kg, supplemented formula-fed; SF) (n = 8), or fed a formula with low amounts of these carotenoids (38.6, 2.3, 21.5, and 0 nmol/kg, unsupplemented formula-fed; UF) (n = 7). The concentrations of carotenoids in serum and tissues were analyzed by HPLC. Results: At 6 mo of age, the BF group exhibited significantly higher lutein concentrations in serum, all brain regions, macular and peripheral retina, adipose tissue, liver, and other tissues compared to both formula-fed groups (P < 0.001). Lutein concentrations were higher in the SF group than in the UF group in serum and all tissues, with the exception of macular retina. Lutein was differentially distributed across brain areas, with the highest concentrations in the occipital cortex, regardless of the diet. Zeaxanthin was present in all brain regions but only in the BF infants; it was present in both retinal regions in all groups but was significantly enhanced in BF infants compared to either formula group (P < 0.001). ß-Carotene accumulated across brain regions in all groups, but was not detected in retina. Although lycopene was found in many tissues of the SF group, it was not detected in the brain or retina. Conclusions: Although carotenoid supplementation of infant formula significantly increased serum and tissue lutein concentrations compared to unsupplemented formula, concentrations were still well below those in BF infants. Regardless of diet, occipital cortex showed selectively higher lutein deposition than other brain regions, suggesting lutein's role in visual processing in early life.

Lutein accumulates in subcellular membranes of brain regions in adult rhesus macaques: Relationship to DHA oxidation products.

OBJECTIVES: Lutein, a carotenoid with anti-oxidant functions, preferentially accumulates in primate brain and is positively related to cognition in humans. Docosahexaenoic acid (DHA), an omega-3 polyunsaturated fatty acid (PUFA), is also beneficial for cognition, but is susceptible to oxidation. The present study characterized the membrane distribution of lutein in brain regions important for different domains of cognitive function and determined whether membrane lutein was associated with brain PUFA oxidation. METHODS: Adult rhesus monkeys were fed a stock diet (~2 mg/day lutein or ~0.5 µmol/kg body weight/day) (n = 9) or the stock diet plus a daily supplement of lutein (~4.5 mg/day or~1 µmol/kg body weight/day) and zeaxanthin (~0.5 mg/day or 0.1 µmol/kg body weight/day) for 6-12 months (n = 4). Nuclear, myelin, mitochondrial, and neuronal plasma membranes were isolated using a Ficoll density gradient from prefrontal cortex (PFC), cerebellum (CER), striatum (ST), and hippocampus (HC). Carotenoids, PUFAs, and PUFA oxidation products were measured using HPLC, GC, and LC-GC/MS, respectively. RESULTS: All-trans-lutein (ng/mg protein) was detected in all regions and membranes and was highly variable among monkeys. Lutein/zeaxanthin supplementation significantly increased total concentrations of lutein in serum, PFC and CER, as well as lutein in mitochondrial membranes and total DHA concentrations in PFC only (P<0.05). In PFC and ST, mitochondrial lutein was inversely related to DHA oxidation products, but not those from arachidonic acid (P <0.05). DISCUSSION: This study provides novel data on subcellular lutein accumulation and its relationship to DHA oxidation in primate brain. These findings support the hypothesis that lutein may be associated with antioxidant functions in the brain.

Supplementation with RRR- or all-rac-α-Tocopherol Differentially Affects the α-Tocopherol Stereoisomer Profile in the Milk and Plasma of Lactating Women.

Background: The naturally occurring α-tocopherol stereoisomer RRR-α-tocopherol is known to be more bioactive than synthetic α-tocopherol (all-rac-α-tocopherol). However, the influence of this difference on the α-tocopherol stereoisomer profile of human milk is not understood.Objective: We investigated whether supplemental RRR-α-tocopherol or all-rac-α-tocopherol differentially affected the distribution of α-tocopherol stereoisomers in milk and plasma from lactating women.Methods: Eighty-nine lactating women aged 19-40 y and with a body mass index (in kg/m2) ≤30 were randomly assigned at 4-6 wk postpartum to receive a daily supplement containing 45.5 mg all-rac-α-tocopherol acetate (ARAC), 22.8 mg all-rac-α-tocopherol acetate + 20.1 mg RRR-α-tocopherol (MIX), or 40.2 mg RRR-α-tocopherol (RRR). Milk and plasma were analyzed for α-tocopherol structural isomers and α-tocopherol stereoisomers at baseline and after 6 wk supplementation with the use of chiral HPLC.Results: There were no significant treatment group or time-dependent changes in milk or plasma α, γ, or δ-tocopherol. RRR-α-tocopherol was the most abundant stereoisomer in both milk and plasma in each group. Supplementation changed both milk and plasma percentage RRR-α-tocopherol (RRR > MIX > ARAC) (P < 0.05) and percentage non-RRR-α-tocopherol (ARAC > MIX > RRR) (P < 0.05). In the RRR group, percentage RRR-α-tocopherol increased in milk (mean ± SEM: 78% ± 2.3% compared with 82% ± 1.7%) (P < 0.05) and plasma (mean ± SEM: 77% ± 1.8% compared with 87% ± 1%) (P < 0.05). In contrast, the percentage RRR-α-tocopherol decreased in the MIX and ARAC groups (MIX, P < 0.05; ARAC, P < 0.0001), and percentage non-RRR-α-tocopherol stereoisomers increased (MIX, P < 0.05; ARAC, P < 0.0001) commensurate with an accumulation of 2S-α-tocopherol stereoisomers (P < 0.05) in both milk and plasma. Milk and plasma RRR-α-tocopherol was positively correlated at baseline (r = 0.67; P < 0.0001) and 6 wk (r = 0.80; P < 0.0001).Conclusion: The α-tocopherol supplementation strategy differentially affected the α-tocopherol milk and plasma stereoisomer profile in lactating women. RRR-α-tocopherol increased milk and plasma percentage RRR-α-tocopherol, whereas all-rac-α-tocopherol acetate reduced these percentages. Because RRR-α-tocopherol is the most bioactive stereoisomer, investigating the impact of supplement-driven changes in the milk α-tocopherol stereoisomer profile on the α-tocopherol status of breastfed infants is warranted.

Effect of Carotenoid Supplemented Formula on Carotenoid Bioaccumulation in Tissues of Infant Rhesus Macaques: A Pilot Study Focused on Lutein.

Lutein is the predominant carotenoid in the developing primate brain and retina, and may have important functional roles. However, its bioaccumulation pattern during early development is not understood. In this pilot study, we investigated whether carotenoid supplementation of infant formula enhanced lutein tissue deposition in infant rhesus macaques. Monkeys were initially breastfed; from 1 to 3 months of age they were fed either a formula supplemented with lutein, zeaxanthin, ß-carotene and lycopene, or a control formula with low levels of these carotenoids, for 4 months (n = 2/group). All samples were analyzed by high pressure liquid chromatography (HPLC). Final serum lutein in the supplemented group was 5 times higher than in the unsupplemented group. All brain regions examined showed a selective increase in lutein deposition in the supplemented infants. Lutein differentially accumulated across brain regions, with highest amounts in occipital cortex in both groups. ß-carotene accumulated, but zeaxanthin and lycopene were undetectable in any brain region. Supplemented infants had higher lutein concentrations in peripheral retina but not in macular retina. Among adipose sites, abdominal subcutaneous adipose tissue exhibited the highest lutein level and was 3-fold higher in the supplemented infants. The supplemented formula enhanced carotenoid deposition in several other tissues. In rhesus infants, increased intake of carotenoids from formula enhanced their deposition in serum and numerous tissues and selectively increased lutein in multiple brain regions.

Carrot solution culture bioproduction of uniformly labeled 13C-lutein and in vivo dosing in non-human primates.

Lutein is a xanthophyll abundant in nature and most commonly present in the human diet through consumption of leafy green vegetables. With zeaxanthin and meso-zeaxanthin, lutein is a component of the macular pigment of the retina, where it protects against photooxidation and age-related macular degeneration. Recent studies have suggested that lutein may positively impact cognition throughout the lifespan, but outside of the retina, the deposition, metabolism, and function(s) of lutein are poorly understood. Using a novel botanical cell culture system ( Daucus carota), the present study aimed to produce a stable isotope lutein tracer for use in future investigations of dietary lutein distribution and metabolism. Carrot cultivars were initiated into liquid solution culture, lutein production conditions optimized, and uniformly labeled 13C-glucose was provided as the sole media carbon source for four serial growth cycles. Lutein yield was 2.58 ± 0.24 µg/g, and mass spectrometry confirmed high enrichment of 13C: 64.9% of lutein was uniformly labeled and 100% of lutein was labeled on at least 37 of 40 possible carbons. Purification of carrot extracts yielded a lutein dose of 1.92 mg with 96.0 ± 0.60% purity. 13C-lutein signals were detectable in hepatic extracts of an adult rhesus macaque monkey ( Macaca mulatta) dosed with 13C-lutein, but not in hepatic samples collected from control animals. This novel botanical biofactory approach can be used to produce sufficient quantities of highly enriched and pure 13C-lutein doses for use in tracer studies investigating lutein distribution, metabolism, and function.

The naturally occurring α-tocopherol stereoisomer RRR-α-tocopherol is predominant in the human infant brain.

α-Tocopherol is the principal source of vitamin E, an essential nutrient that plays a crucial role in maintaining healthy brain function. Infant formula is routinely supplemented with synthetic α-tocopherol, a racaemic mixture of eight stereoisomers with less bioactivity than the natural stereoisomer RRR-α-tocopherol. α-Tocopherol stereoisomer profiles have not been previously reported in the human brain. In the present study, we analysed total α-tocopherol and α-tocopherol stereoisomers in the frontal cortex (FC), hippocampus (HPC) and visual cortex (VC) of infants (n 36) who died of sudden infant death syndrome or other conditions. RRR-α-tocopherol was the predominant stereoisomer in all brain regions (P<0·0001) and samples, despite a large intra-decedent range in total α-tocopherol (5-17 µg/g). Mean RRR-α-tocopherol concentrations in FC, HPC and VC were 10·5, 6·8 and 5·5 µg/g, respectively. In contrast, mean levels of the synthetic stereoisomers were RRS, 1-1·5; RSR, 0·8-1·0; RSS, 0·7-0·9; and Σ2S 0·2-0·3 µg/g. Samples from all but two decedents contained measurable levels of the synthetic stereoisomers, but the intra-decedent variation was large. The ratio of RRR:the sum of the synthetic 2R stereoisomers (RRS+RSR+RSS) averaged 2·5, 2·3 and 2·4 in FC, HPC and VC, respectively, and ranged from 1 to at least 4·7, indicating that infant brain discriminates against synthetic 2R stereoisomers in favour of RRR. These findings reveal that RRR-α-tocopherol is the predominant stereoisomer in infant brain. These data also indicate that the infant brain discriminates against the synthetic 2R stereoisomers, but is unable to do so completely. On the basis of these findings, investigation into the impact of α-tocopherol stereoisomers on neurodevelopment is warranted.

Exploratory Metabolomic Analyses Reveal Compounds Correlated with Lutein Concentration in Frontal Cortex, Hippocampus, and Occipital Cortex of Human Infant Brain.

Lutein is a dietary carotenoid well known for its role as an antioxidant in the macula, and recent reports implicate a role for lutein in cognitive function. Lutein is the dominant carotenoid in both pediatric and geriatric brain tissue. In addition, cognitive function in older adults correlated with macular and postmortem brain lutein concentrations. Furthermore, lutein was found to preferentially accumulate in the infant brain in comparison to other carotenoids that are predominant in diet. While lutein is consistently related to cognitive function, the mechanisms by which lutein may influence cognition are not clear. In an effort to identify potential mechanisms through which lutein might influence neurodevelopment, an exploratory study relating metabolite signatures and lutein was completed. Post-mortem metabolomic analyses were performed on human infant brain tissues in three regions important for learning and memory: the frontal cortex, hippocampus, and occipital cortex. Metabolomic profiles were compared to lutein concentration, and correlations were identified and reported here. A total of 1276 correlations were carried out across all brain regions. Of 427 metabolites analyzed, 257 were metabolites of known identity. Unidentified metabolite correlations (510) were excluded. In addition, moderate correlations with xenobiotic relationships (2) or those driven by single outliers (3) were excluded from further study. Lutein concentrations correlated with lipid pathway metabolites, energy pathway metabolites, brain osmolytes, amino acid neurotransmitters, and the antioxidant homocarnosine. These correlations were often brain region-specific. Revealing relationships between lutein and metabolic pathways may help identify potential candidates on which to complete further analyses and may shed light on important roles of lutein in the human brain during development.