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Wang D, Shahab-Ferdows S, Lweno ON, Hampel D, Method B, Yelverton CA, Nguyen CH, Aboud S, Allen LH, Fawzi WW. The effects of prenatal and postnatal high-dose vitamin B-12 supplementation on human milk vitamin B-12: a randomized, double-blind, placebo-controlled trial in Tanzania. Am J Clin Nutr 2024; 119:730-739. [PMID: 38432714 DOI: 10.1016/j.ajcnut.2023.07.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 07/17/2023] [Accepted: 07/31/2023] [Indexed: 03/05/2024] Open
Abstract
BACKGROUND Vitamin B-12 status in human milk (HM) has critical implications for infant growth and development. Few studies have separately evaluated the effects of prenatal and postnatal maternal high-dose vitamin B-12 supplementation on HM vitamin B-12 concentration. OBJECTIVES This randomized controlled trial aimed to assess the effects of prenatal and postnatal vitamin B-12 supplementation on HM vitamin B-12 at 6 wk and 7 mo postpartum. METHODS Pregnant women were enrolled in Dar es Salaam, Tanzania, between 2001 and 2004. From recruitment (12-27 weeks of gestation) through 6 wk postpartum, participants were randomly assigned to daily oral multiple micronutrient supplementation or placebo. From 6 wk to 18 mo postpartum, a subset of participants was randomly assigned to a postnatal supplement or placebo. The supplement included 50 μg/d of vitamin B-12 and various other vitamins. HM vitamin B-12 concentrations were analyzed at 6 wk and 7 mo postpartum for 412 participants. RESULTS The prevalence of HM vitamin B-12 of <310 pmol/L was 73.3% and 68.4% at 6 wk and 7 mo postpartum, respectively. Prenatal supplementation increased HM vitamin B-12 concentration (percent difference: 34.4; 95% CI: 17.0, 54.5; P < 0.001) at 6 wk; this effect was not present at 7 mo. Postnatal supplementation increased HM vitamin B-12 concentration (percent difference: 15.9; 95% CI: 1.91, 31.9; P = 0.025) at 7 mo. Effect modification between prenatal and postnatal supplementation on HM vitamin B-12 status at 7 mo was found, with the effects of prenatal and postnatal supplements more pronounced among those receiving control during the other period; the prenatal supplement had a greater effect with postnatal control, and the postnatal supplement had a greater effect with prenatal control. CONCLUSIONS Prenatal maternal vitamin B-12 supplementation has benefits on short-term HM status, and postnatal maternal vitamin B-12 supplementation has benefits on long-term HM status. This trial was registered at clinicaltrials.gov as NCT00197548. https://clinicaltrials.gov/ct2/show/NCT00197548.
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Affiliation(s)
- Dongqing Wang
- Department of Global and Community Health, College of Public Health, George Mason University, Fairfax, VA, United States.
| | - Setareh Shahab-Ferdows
- Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA, United States
| | - Omar N Lweno
- Ifakara Health Institute, Bagamoyo Research and Training Center, Bagamoyo, Tanzania
| | - Daniela Hampel
- Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA, United States; Department of Nutrition, University of California, Davis, CA, United States
| | - Balama Method
- Department of Microbiology and Immunology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Cara A Yelverton
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, United States
| | - Christine H Nguyen
- Department of Global and Community Health, College of Public Health, George Mason University, Fairfax, VA, United States
| | - Said Aboud
- Department of Microbiology and Immunology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Lindsay H Allen
- Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA, United States
| | - Wafaie W Fawzi
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, United States; Department of Nutrition, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, United States; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, United States
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Intake of Vitamin B12 and Folate and Biomarkers of Nutrient Status of Women within Two Years Postpartum. Nutrients 2022; 14:nu14183869. [PMID: 36145245 PMCID: PMC9505829 DOI: 10.3390/nu14183869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 09/14/2022] [Accepted: 09/16/2022] [Indexed: 11/25/2022] Open
Abstract
Background: Little is known about variation in vitamin B12 and folate status among Chinese women 2 years postpartum. This study assessed intake of vitamin B12 and folate and biomarkers of nutrient status among Chinese women postpartum. Methods: Demographic information, multi-/single-nutrient supplementation, dietary data, serum vitamin B12 and serum folate were assessed in 982 women within 2 years postpartum, using ten investigation sites in Zhejiang Province from the National Nutritional Study 2016−2017, which is a nationally representative cross-sectional study, to form a representative provincial sample of Zhejiang Province. The dietary diversity score (DDS) was used for assessing the dietary pattern. Results: Vitamin B12 increased slightly at the early stage of postpartum and then dropped over time. Serum folate level elevated with postpartum time. The median serum vitamin B12 concentration was 494.59 (373.21−650.20) pg/mL, and folate was 7.58 (5.02−10.34) ng/mL. Correspondingly, vitamin B12 levels suggesting marginal deficiency (200−300 pg/mL) and deficiency (<200 pg/mL) resulted as 9.27% and 3.26%, respectively, and folate level suggesting deficiency (<3 ng/mL) was 9.16%. Multi-/single-nutrient supplementation during pregnancy was associated with log-transformed serum vitamin B12 and folate level after adjusting for potential confounders (vitamin B12: ß (SE) = 0.124 (0.028), p < 0.001; folate: 0.128 (0.035), <0.001). Additionally, postpartum nutrient supplementation was associated with log-transformed serum folate level, especially for lactating women (ß (SE) = 0.204 (0.062), p = 0.001). Increased DDS was significantly associated with elevated serum vitamin B12 and folate levels (vitamin B12: ß (SE) = 0.028 (0.011), p = 0.011; folate: 0.030 (0.014), 0.031). In addition, age and educational level were influencing factors for serum vitamin B12 and folate concentrations among postpartum women. Conclusion: Serum vitamin B12 level decreased and folate level increased with postpartum age among Chinese women. Nutrient supplementation during pregnancy was related to elevated serum vitamin B12 and folate concentrations. Postpartum nutrient supplementation was associated with the increased serum folate level of lactating women. Dietary diversity was related to increased serum vitamin B12 and folate levels, especially among postpartum women with younger age and lower educational level.
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Shinde S, Wang D, Yussuf MH, Mwanyika-Sando M, Aboud S, Fawzi WW. Micronutrient Supplementation for Pregnant and Lactating Women to Improve Maternal and Infant Nutritional Status in Low- and Middle-Income Countries: Protocol for a Systematic Review and Meta-analysis. JMIR Res Protoc 2022; 11:e40134. [PMID: 36040761 PMCID: PMC9472043 DOI: 10.2196/40134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 07/08/2022] [Accepted: 07/14/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Two billion people in low- and middle-income countries (LMICs) are deficient in key nutrients. Nutritional deficiencies worsen during pregnancy, causing adverse outcomes for the mother and the fetus, with consequences after pregnancy. These effects may be mitigated by providing micronutrient supplementation to women during pregnancy and lactation. However, the effects of micronutrient supplementation on the nutritional status of pregnant and lactating women and that of their infants remain largely unclear in LMICs. OBJECTIVE The purpose of this systematic review and meta-analysis is to determine the effects of single, double, or multiple micronutrient supplements during pregnancy or lactation on maternal and infant nutritional status in LMICs. METHODS Randomized controlled trials of single, double, or combinations of micronutrients assessing effects on the maternal (serum, plasma, and breastmilk) and infant (serum and plasma) nutritional status will be included. MEDLINE (through PubMed), EMBASE, CENTRAL (through Cochrane Library), and the World Health Organization (WHO) library database will be used to identify relevant published studies, starting from the inception of each database until February 28, 2022. The Cochrane Risk of Bias Tool will be used to assess the risk of bias in the included studies. The selection of studies, data extraction, and risk of bias assessment will be carried out independently by 2 reviewers. A narrative summary will be provided of all the included studies. Meta-analyses will be performed whenever possible, and the heterogeneity of effects will be evaluated using I2, subgroup analyses, and metaregression. The certainty of the evidence for each outcome will be assessed using the GRADE (Grading of Recommendation, Assessment, Development, and Evaluation) approach. RESULTS We will conduct meta-analyses using Stata software (version 16, StataCorp) and present both a narrative and systematic summary of all studies included in this review in text and table form. For continuous outcomes, effect estimates will be expressed as mean differences and standardized mean differences, while for binary outcomes, they will be expressed as risk ratios, rate ratios, hazards ratios, or odds ratios, all with 95% CIs and comparing the intervention group with the control group. When studies for an outcome are adequately consistent with respect to intervention, comparator, and definition of the outcome, a random-effects, inverse variance-weighted meta-analysis will be conducted. We will provide a narrative synthesis for outcomes with insufficient data or extreme heterogeneity. CONCLUSIONS This review will provide evidence upon which to base policy and programming for women in LMICs to supplement micronutrients in pregnancy and lactation. Detailed results disaggregated by variables such as maternal age, sex of infant, duration, and dose of intervention may also help policy makers, researchers, practitioners, and government agencies to adopt more effective maternal and child health policies and programs in LMICs. The review will also identify any gaps in the existing evidence. TRIAL REGISTRATION PROSPERO CRD42022308715; https://tinyurl.com/y33cxekr. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) PRR1-10.2196/40134.
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Affiliation(s)
- Sachin Shinde
- T H Chan School of Public Health, Harvard University, Boston, MA, United States
| | - Dongqing Wang
- T H Chan School of Public Health, Harvard University, Boston, MA, United States
| | - Mashavu H Yussuf
- Africa Academy for Public Health, Dar es Salaam, United Republic of Tanzania
| | - Mary Mwanyika-Sando
- Africa Academy for Public Health, Dar es Salaam, United Republic of Tanzania
| | - Said Aboud
- Department of Microbiology and Immunology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, United Republic of Tanzania
| | - Wafaie W Fawzi
- T H Chan School of Public Health, Harvard University, Boston, MA, United States
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Watanabe F, Bito T, Koseki K. Determination of cobalamin and related compounds in foods. VITAMINS AND HORMONES 2022; 119:491-504. [PMID: 35337633 DOI: 10.1016/bs.vh.2022.01.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The microbiological assay of total cobalamin (vitamin B12) by Lactobacillus delbrueckii subsp. lactis ATCC7830 is now used worldwide in food analysis because of its high sensitivity, low running cost, and no expensive instruments. It has been recently reported that some foods contain a substantial number of inactive corrinoid compounds, some of which are active in this bacterium. These results indicate that the microbiological method must be replaced with high-performance liquid chromatography or liquid chromatography/electrospray ionization-tandem mass spectrometry as there can specifically determine biologically active cobalamin. Nowadays, powerful tools, such as immunoaffinity columns, purify cobalamin simply and specifically. In this chapter, we summarized the determination methods of cobalamin and related compounds in foods. Various inactive corrinoids found in foods were also characterized.
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Affiliation(s)
- F Watanabe
- Division of Applied Bioresource Chemistry, United Graduate School of Agricultural Sciences, Tottori University, Tottori, Japan; Department of Agricultural, Life and Environmental Sciences, Faculty of Agriculture, Tottori University, Tottori, Japan.
| | - T Bito
- Division of Applied Bioresource Chemistry, United Graduate School of Agricultural Sciences, Tottori University, Tottori, Japan; Department of Agricultural, Life and Environmental Sciences, Faculty of Agriculture, Tottori University, Tottori, Japan
| | - K Koseki
- Division of Applied Bioresource Chemistry, United Graduate School of Agricultural Sciences, Tottori University, Tottori, Japan
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Batalha MA, Ferreira ALL, Freitas-Costa NC, Figueiredo ACC, Carrilho TRB, Shahab-Ferdows S, Hampel D, Allen LH, Pérez-Escamilla R, Kac G. Factors associated with longitudinal changes in B-vitamin and choline concentrations of human milk. Am J Clin Nutr 2021; 114:1560-1573. [PMID: 34113959 DOI: 10.1093/ajcn/nqab191] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 05/17/2021] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Little is known regarding the associations between maternal factors and B-vitamin and choline concentrations in early milk and the trajectories of these vitamins during lactation. OBJECTIVES In this hypothesis-generating study, we modeled the association between maternal and offspring factors and longitudinal changes in milk B-vitamin and choline concentrations throughout lactation. METHODS A hundred women were studied in a prospective birth cohort and milk samples from 52 women were collected at 2-8 d, 76 women at 28-50 d, and 42 women at 88-119 d postpartum. Maternal dietary intake during pregnancy and lactation was assessed by an FFQ. Linear mixed-effects models with interaction terms were used to evaluate changes in milk B-vitamin and choline concentrations over time based on maternal factors and the early postpartum concentrations of these micronutrients. RESULTS The women with higher early postpartum milk concentrations of niacin (βinteraction = -0.02; SE = 0.00; P < 0.001), pantothenic acid (βinteraction = -0.10; SE = 2.56; P < 0.001), vitamin B-12 (βinteraction= -0.10; SE = 0.03; P < 0.001), and choline (βinteraction= -0.90; SE = 0.18; P < 0.001) exhibited a decrease in their concentrations throughout lactation. The participants with overweight and obesity prepregnancy experienced an increase in milk vitamin B-12 concentrations over time (βinteraction = 0.04; SE = 0.02; P = 0.06). In contrast, a decrease in vitamin B-12 concentration was observed among women with vitamin B-12 intake below the RDA during pregnancy (βinteraction= -0.08; SE = 0.05; P = 0.07). The women with niacin intake below the RDA during lactation experienced an increase in milk concentrations over time (βinteraction = 0.01; SE = 0.01; P = 0.03). A gestational age at birth >40 wk was associated with an increase in milk choline concentration throughout lactation (βinteraction = 0.54; SE = 0.16; P< 0.01). CONCLUSIONS Changes in B-vitamin and choline concentrations in human milk over time may be associated with the early concentrations of these micronutrients in milk, maternal prepregnancy BMI, dietary intake, and gestational age at delivery.
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Affiliation(s)
- Mônica A Batalha
- Nutritional Epidemiology Observatory, Josué de Castro Nutrition Institute, Rio de Janeiro Federal University, Rio de Janeiro, Brazil
| | - Ana L L Ferreira
- Nutritional Epidemiology Observatory, Josué de Castro Nutrition Institute, Rio de Janeiro Federal University, Rio de Janeiro, Brazil
| | - Nathalia C Freitas-Costa
- Nutritional Epidemiology Observatory, Josué de Castro Nutrition Institute, Rio de Janeiro Federal University, Rio de Janeiro, Brazil
| | - Amanda C C Figueiredo
- Nutritional Epidemiology Observatory, Josué de Castro Nutrition Institute, Rio de Janeiro Federal University, Rio de Janeiro, Brazil
| | - Thais R B Carrilho
- Nutritional Epidemiology Observatory, Josué de Castro Nutrition Institute, Rio de Janeiro Federal University, Rio de Janeiro, Brazil
| | - Setareh Shahab-Ferdows
- USDA/Agricultural Research Service Western Human Nutrition Research Center, Davis, CA, USA
| | - Daniela Hampel
- USDA/Agricultural Research Service Western Human Nutrition Research Center, Davis, CA, USA.,Department of Nutrition, University of California, Davis, Davis, CA, USA
| | - Lindsay H Allen
- USDA/Agricultural Research Service Western Human Nutrition Research Center, Davis, CA, USA.,Department of Nutrition, University of California, Davis, Davis, CA, USA
| | - Rafael Pérez-Escamilla
- Department of Social and Behavioral Sciences, Yale School of Public Health, New Haven, CT, USA
| | - Gilberto Kac
- Nutritional Epidemiology Observatory, Josué de Castro Nutrition Institute, Rio de Janeiro Federal University, Rio de Janeiro, Brazil
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van Huis A, Rumpold B, Maya C, Roos N. Nutritional Qualities and Enhancement of Edible Insects. Annu Rev Nutr 2021; 41:551-576. [PMID: 34186013 DOI: 10.1146/annurev-nutr-041520-010856] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Over the last decade, the urgency to find alternative and sustainable protein sources has prompted an exponential increase in the interest in insects as a human food source. Edible insects contribute suitable amounts of energy and protein, fatty acids, and micronutrients to the human diet. Nutritional values of insects can be manipulated to meet specific needs. Edible insects in food-insecure countries can contribute to improving diets and preventing undernutrition. Bioactive compounds in insects may reduce health risks. Food safety risks are low and mainly relate to those of allergenicity. Strategies to overcome barriers to the consumption of insect products include emphasizing their sustainability, increasing their tastiness, and developing the ability to disguise insects in familiar products. A new sector of insects as food and feed is emerging. Major challenges include legislation, lowering prices by automation and cheap substrates, developing insect products that appeal to consumers, and exploring the health benefits. Expected final online publication date for the Annual Review of Nutrition, Volume 41 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Arnold van Huis
- Laboratory of Entomology, Wageningen University & Research, 6708 PB Wageningen, The Netherlands;
| | - Birgit Rumpold
- Department of Education for Sustainable Nutrition and Food Science, Technische Universität Berlin, 10587 Berlin, Germany;
| | - Cassandra Maya
- Department of Nutrition, Exercise and Sports, University of Copenhagen, 1958 Frederiksberg C, Denmark; ,
| | - Nanna Roos
- Department of Nutrition, Exercise and Sports, University of Copenhagen, 1958 Frederiksberg C, Denmark; ,
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Wang D, Natchu UCM, Darling AM, Noor RA, Hertzmark E, Urassa W, Fawzi WW. Effects of prenatal and postnatal maternal multiple micronutrient supplementation on child growth and morbidity in Tanzania: a double-blind, randomized-controlled trial. Int J Epidemiol 2021; 51:1761-1774. [PMID: 34151973 PMCID: PMC9749718 DOI: 10.1093/ije/dyab117] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 05/20/2021] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Maternal micronutrient status is critical for child growth and nutrition. It is unclear whether maternal multiple micronutrient supplementation (MMS) during pregnancy and lactation improves child growth and prevents child morbidity. METHODS This study aimed to determine the effects of prenatal and postnatal maternal MMS on child growth and morbidity. In this double-blind, randomized-controlled trial, 8428 HIV-negative pregnant women were enrolled from Dar es Salaam, Tanzania, between 2001 and 2004. From pregnancy (12-27 weeks of gestation) through to 6 weeks postpartum, participants were randomized to receive daily oral MMS or placebo. All women received daily iron and folic acid during pregnancy. From 6 weeks postpartum through to 18 months postpartum, 3100 women were re-randomized to MMS or placebo. Child-growth measures, haemoglobin concentrations and infectious morbidities were assessed longitudinally from birth to ≤18 months. RESULTS Prenatal MMS led to modest increases in weight-for-age z-scores (mean difference: 0.050; 95% confidence interval: 0.002, 0.099; p = 0.04) and length-for-age z-score (mean difference: 0.062; 95% confidence interval: 0.013, 0.111; p = 0.01) during the first 6 months of life but not thereafter. Prenatal or postnatal MMS did not have benefits for other child outcomes. CONCLUSIONS Whereas maternal MMS is a proven strategy to prevent adverse birth outcomes, other approaches may also need to be considered to curb the high burdens of child morbidity and growth faltering.
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Affiliation(s)
- Dongqing Wang
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
| | | | - Anne Marie Darling
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
| | - Ramadhani A Noor
- United Nations Children's Fund Tanzania, Dar es Salaam, Tanzania
| | - Ellen Hertzmark
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
| | - Willy Urassa
- Department of Microbiology and Immunology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Wafaie W Fawzi
- Corresponding author. Harvard T.H. Chan School of Public Health, 665 Huntington Avenue, Building 1, Room 1102, Boston, MA 02115, USA. E-mail:
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Boachie J, Adaikalakoteswari A, Goljan I, Samavat J, Cagampang FR, Saravanan P. Intracellular and Tissue Levels of Vitamin B12 in Hepatocytes Are Modulated by CD320 Receptor and TCN2 Transporter. Int J Mol Sci 2021; 22:3089. [PMID: 33803025 PMCID: PMC8002616 DOI: 10.3390/ijms22063089] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/10/2021] [Accepted: 03/14/2021] [Indexed: 11/17/2022] Open
Abstract
The liver mass constitutes hepatocytes expressing receptors for vitamin B12 (B12)-bound transporters in circulation. However, intrahepatic and circulating B12 interrelationship levels remain unclear. We assessed the intracellular B12 levels at various circulating B12 concentrations in human HepG2 cell-line and liver tissue levels of B12 in the C57BL/6 mouse model. In HepG2 cells treated with a range of B12 concentrations, the intracellular and circulatory B12 levels, transcript and protein levels of B12 receptor (CD320) and transporter (TCN2) were determined using immunoassays, qRT-PCR and Western blot, respectively. Similar assessments were done in plasma and liver tissue of C57BL/6 mice, previously fed a diet of either a high or low B12 (30.82 µg B12/kg and 7.49 µg B12/kg, respectively) for 8-10 weeks. The physiological B12 status (0.15-1 nM) resulted in increased levels of intracellular B12 in HepG2 cells compared to supraphysiological levels of B12 (>1 nM). Gene and protein expression of CD320 and TCN2 were also higher at physiological levels of B12. Progressively increasing extracellular B12 to supraphysiological levels led to relative decreased levels of intracellular B12, lower expression of gene and protein levels of CD320 and TCN2. Similar results were observed in liver tissue from mice fed on a low B12 diet verses high B12 diet. These findings suggest that unlike supraphysiological B12, physiological levels of B12 in the extracellular media or circulation accelerates active transport of B12, and expression of CD320 and TCN2, resulting in higher relative uptake of B12 in hepatocytes.
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Affiliation(s)
- Joseph Boachie
- Division of Metabolic and Vascular Health, Warwick Medical School, University of Warwick, Coventry CV2 2DX, UK; (J.B.); (J.S.)
| | - Antonysunil Adaikalakoteswari
- Division of Metabolic and Vascular Health, Warwick Medical School, University of Warwick, Coventry CV2 2DX, UK; (J.B.); (J.S.)
- Department of Biosciences, School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS, UK
| | - Ilona Goljan
- Diabetes Centre, George Eliot Hospital NHS Trust College Street, Nuneaton CV10 7DJ, UK;
| | - Jinous Samavat
- Division of Metabolic and Vascular Health, Warwick Medical School, University of Warwick, Coventry CV2 2DX, UK; (J.B.); (J.S.)
| | - Felino R. Cagampang
- Institute of Developmental Sciences, University of Southampton, Faculty of Medicine, Southampton General Hospital, Southampton SO16 6YD, UK;
| | - Ponnusamy Saravanan
- Division of Metabolic and Vascular Health, Warwick Medical School, University of Warwick, Coventry CV2 2DX, UK; (J.B.); (J.S.)
- Diabetes Centre, George Eliot Hospital NHS Trust College Street, Nuneaton CV10 7DJ, UK;
- Division of Health Sciences, Warwick Medical School, University of Warwick, Coventry CV2 2DX, UK
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