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Associations of Genetically Predicted Vitamin B 12 Status across the Phenome. Nutrients 2022; 14:nu14235031. [PMID: 36501061 PMCID: PMC9740080 DOI: 10.3390/nu14235031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/16/2022] [Accepted: 11/24/2022] [Indexed: 11/29/2022] Open
Abstract
Variation in vitamin B12 levels has been associated with a range of diseases across the life-course, the causal nature of which remains elusive. We aimed to interrogate genetically predicted vitamin B12 status in relation to a plethora of clinical outcomes available in the UK Biobank. Genome-wide association study (GWAS) summary data obtained from a Danish and Icelandic cohort of 45,576 individuals were used to identify 8 genetic variants associated with vitamin B12 levels, serving as genetic instruments for vitamin B12 status in subsequent analyses. We conducted a Mendelian randomisation (MR)-phenome-wide association study (PheWAS) of vitamin B12 status with 945 distinct phenotypes in 439,738 individuals from the UK Biobank using these 8 genetic instruments to proxy alterations in vitamin B12 status. We used external GWAS summary statistics for replication of significant findings. Correction for multiple testing was taken into consideration using a 5% false discovery rate (FDR) threshold. MR analysis identified an association between higher genetically predicted vitamin B12 status and lower risk of vitamin B deficiency (including all B vitamin deficiencies), serving as a positive control outcome. We further identified associations between higher genetically predicted vitamin B12 status and a reduced risk of megaloblastic anaemia (OR = 0.35, 95% CI: 0.20-0.50) and pernicious anaemia (0.29, 0.19-0.45), which was supported in replication analyses. Our study highlights that higher genetically predicted vitamin B12 status is potentially protective of risk of vitamin B12 deficiency associated with pernicious anaemia diagnosis, and reduces risk of megaloblastic anaemia. The potential use of genetically predicted vitamin B12 status in disease diagnosis, progression and management remains to be investigated.
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Dib MJ, Gumban-Marasigan M, Yoxall R, Andrew T, Harrington DJ, Sobczyńska-Malefora A, Ahmadi KR. Evaluating the Diagnostic Value of a Combined Indicator of Vitamin B12 Status (cB12) Throughout Pregnancy. Front Nutr 2022; 8:789357. [PMID: 35155515 PMCID: PMC8825834 DOI: 10.3389/fnut.2021.789357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/03/2021] [Indexed: 11/15/2022] Open
Abstract
Background Inadequate provision of vitamin B12 during pregnancy is associated with a number of adverse maternal and fetal outcomes. We set out to (1) suggest pregnancy-specific reference ranges for a range of biomarkers of vitamin B12; (2) assess the temporal behaviors of these markers over the course of pregnancy; and (3) test whether any biomarkers, including the genetic marker HIBCH rs291466 strongly associated with MMA measured early in pregnancy could reliably and significantly predict future B12 status within a healthy UK population of pregnant women. Materials and Methods We used existing biobank samples from the placebo arm of the UK Selenium in PRegnancy Intervention (SPRINT) study, to generate biochemical data for serum folate, B12, holotranscobalamin (HoloTC), total homocysteine (tHcy), and MMA, calculate cB12, and genotyped the polymorphism rs291466 in gene HIBCH on a total of n=114 women across trimesters 1–3 of their pregnancy. We performed a series of exploratory cross-sectional and longitudinal analyses to investigate levels at each trimester, suggest references ranges, evaluate changes and correlations between the B12 biomarkers, and assess the predictive capabilities of each biomarker from 12-weeks to 35-weeks of gestation. Results Significant changes in all vitamin B12 biomarker values were observed over the three trimesters (P < 0.05). Our study shows that cB12 values were largely constant and stable throughout trimester 1 (T1) and T2 (i.e., up to week 20), but declined significantly in T3 (−66% | P < 0.001). Yet, cB12 generally remained within the normal boundaries. We identified pregnancy and trimester-specific reference ranges for each biomarker at each trimester, notably for total serum B12. This marker fell below the recommended cut-offs in 1/3 of the cohort at the third trimester, contrasting other markers (mostly normal). Our multivariate analyses indicated that none of the biomarkers could reliably and accurately predict any other biomarkers than themselves later in pregnancy. Yet, HoloTC seems to be a promising predictor within the limitations of our cohort, constituted of B12-replete individuals. Most notably, cB12 did not significantly predict itself between trimesters. Finally, we show that the HIBCH variant has little predictive power for MMA or cB12 as it does not explain the significant increase in MMA concentrations nor the decline of cB12 throughout pregnancy. Conclusion Trimester-specific reference ranges for biomarkers of vitamin B12 in normal pregnancy are suggested. However, these biomarkers have limited predictive value in identifying mothers at elevated risk of vitamin B12 insufficiency/deficiency during pregnancy.
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Affiliation(s)
- Marie-Joe Dib
- Department of Nutritional Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
- Department of Biostatistics and Epidemiology, School of Public Health, Imperial College, London, United Kingdom
- *Correspondence: Marie-Joe Dib
| | | | - Rozzie Yoxall
- Department of Nutritional Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
| | - Toby Andrew
- Department of Genomics of Common Disease, Imperial College, London, United Kingdom
| | - Dominic J. Harrington
- The Nutristasis Unit, Viapath, St. Thomas' Hospital, London, United Kingdom
- Division of Women's Health, School of Medicine, King's College London, London, United Kingdom
| | - Agata Sobczyńska-Malefora
- The Nutristasis Unit, Viapath, St. Thomas' Hospital, London, United Kingdom
- Faculty of Life Sciences & Medicine, King's College London, London, United Kingdom
| | - Kourosh R. Ahmadi
- Department of Nutritional Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, United Kingdom
- Kourosh R. Ahmadi
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Torrez M, Chabot-Richards D, Babu D, Lockhart E, Foucar K. How I investigate acquired megaloblastic anemia. Int J Lab Hematol 2022; 44:236-247. [PMID: 34981651 DOI: 10.1111/ijlh.13789] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 10/20/2021] [Indexed: 12/01/2022]
Abstract
In this review of megaloblastic anemia (MA), an overview of vitamin B12 and folate body requirements, biochemical pathways, and laboratory testing strategies will be provided. However, the focus of this review is the classic and unique features of MA in blood and bone marrow. Acquired MA is a benign disorder for many, but can be detrimental for some. The clinical presentation can vary considerably, and the spectrum of symptoms and signs is diverse and quite broad. Prompt recognition and therapy are critical to prevent potential irreversible damage and clinical sequelae, especially in patients with vitamin B12 deficiency. A delay in diagnosis of vitamin B12 deficiency can result in significant neurologic sequelae that may not fully resolve with treatment, including in neonates and young infants. The blood and bone marrow features in MA can closely mimic thrombocytopenic purpura, myelodysplasia, and other myeloid neoplasms. Both pancytopenia and normal MCV at presentation are common in MA and raise unique challenges for the diagnostician. Partially treated MA is also a significant diagnostic "trap". MA is highly responsive to treatment, and patients tend to improve rapidly upon treatment initiation. However, the broad range of clinical and hematologic features makes the rapid, successful diagnosis of MA a unique challenge for the hematopathologist. Even in the era of state-of-the-art laboratory testing, a high suspicion is required.
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Affiliation(s)
- Mary Torrez
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
| | - Devon Chabot-Richards
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
| | - Daniel Babu
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
| | - Evelyn Lockhart
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
| | - Kathryn Foucar
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA
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Maher A, Sobczyńska-Malefora A. The Relationship Between Folate, Vitamin B12 and Gestational Diabetes Mellitus With Proposed Mechanisms and Foetal Implications. J Family Reprod Health 2021; 15:141-149. [PMID: 34721605 PMCID: PMC8536822 DOI: 10.18502/jfrh.v15i3.7131] [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] [Indexed: 11/24/2022] Open
Abstract
The incidence of gestational diabetes mellitus (GDM) is rising, which warrants attention due to the associated complications during pregnancy and in the long term for both mother and offspring. Studies have suggested a relationship between maternal folate (vitamin B9) and vitamin B12 status and GDM risk. Seemingly the most problematic scenario occurs when there is B-vitamin imbalance, with high folate and low vitamin B12. This nutritional state can occur in vitamin B12 deficient women who exceed the recommended folic acid supplementation. However, the pathological mechanisms behind this relationship are currently unclear and are explored in this review article. A high folate/low B12 can lead to a functional folate deficiency through the methyl-trap phenomenon, impairing re-methylation of homocysteine and regeneration of folates for DNA synthesis and repair. Consequently elevated homocysteine concentration leads to endothelial dysfunction and oxidative stress. Vitamin B12 deficiency also leads to an impairment of the conversion of methylmalonyl-CoA to succinyl-CoA, which has been associated with insulin resistance. Insulin resistance is thought to contribute to the etiology of GDM. More studies are needed to confirm the impact of these and other mechanisms on disease development. However, it highlights a potential avenue for GDM risk modification through a vitamin B12 supplement and improvement of maternal metabolic health.
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Affiliation(s)
- Angeline Maher
- Edinburgh Medical School, University of Edinburgh, Edinburgh, UK
| | - Agata Sobczyńska-Malefora
- Faculty of Life Sciences & Medicine, Kings College London, London, UK.,Nutristasis Unit, Viapath, St. Thomas' Hospital, London, UK
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Mineva EM, Sternberg MR, Bailey RL, Storandt RJ, Pfeiffer CM. Fewer US adults had low or transitional vitamin B12 status based on the novel combined indicator of vitamin B12 status compared with individual, conventional markers, NHANES 1999-2004. Am J Clin Nutr 2021; 114:1070-1079. [PMID: 33963731 PMCID: PMC11066312 DOI: 10.1093/ajcn/nqab122] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 03/23/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Elevated plasma methylmalonic acid (MMA) and/or total homocysteine (tHcy), as well as low serum vitamin B12 and/or holotranscobalamin (holoTC) are indicative of vitamin B12 deficiency. Combined indicators (cB12), which pool some or all 4 markers into an index, may be a more reliable diagnostic tool to overcome inconclusive diagnoses with individual markers. OBJECTIVES We aimed to describe different cB12 score combinations and estimate the prevalence of low or transitional vitamin B12 status compared with individual markers. DESIGN Using cross-sectional data for B12, MMA, and tHcy in persons ≥20 y participating in NHANES 1999-2004 (n = 12,335), we examined raw and covariate-adjusted regression models to assess determinants of 3cB12 (all 3 markers) and combinations of 2cB12 (2 markers). RESULTS 3cB12 was significantly associated with B12 (Spearman r = 0.75), MMA (r = -0.70), and tHcy (r = -0.59). The 3cB12 reference interval (2.5th to 97.5th percentile) was -0.538 to 1.60. In covariate-adjusted models, we found no association of 3cB12 with age; adult females and users of B12 supplements had higher, while adults with advanced chronic kidney disease had lower 3cB12 levels regardless of race-Hispanic origin group (self-reported). Only 2.7% of adults had low or transitional vitamin B12 status using the proposed cB12 cutoff of ≤-0.5, while the prevalence of low (or low-normal) status depended on the selected individual marker and its cutoff: 2.2% and 13% for B12 < 148 and 148-222 pmol/L, respectively; 6.0% for MMA exceeding an age-specific cutoff (250-320 nmol/L); and 8.4% for tHcy > 13 µmol/L. The reference intervals for B12, MMA, and tHcy overlapped from the low (<-2.5) to the transitional (-2.5 to -0.5) and to the adequate (>-0.5) cB12 categories. CONCLUSIONS Vitamin B12 deficiency may be overestimated among US adults when individual, conventional markers are used. When only 2 markers are available, the combination of B12 and MMA provides results comparable to 3cB12.
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Affiliation(s)
- Ekaterina M Mineva
- Centers for Disease Control and Prevention (CDC), National Center for Environmental Health, Atlanta, GA, USA
| | - Maya R Sternberg
- Centers for Disease Control and Prevention (CDC), National Center for Environmental Health, Atlanta, GA, USA
| | - Regan L Bailey
- Department of Nutrition Science, Purdue University, West Lafayette, IN, USA
| | - Renee J Storandt
- CDC, National Center for Health Statistics, Hyattsville, MD, USA
| | - Christine M Pfeiffer
- Centers for Disease Control and Prevention (CDC), National Center for Environmental Health, Atlanta, GA, USA
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Sobczyńska-Malefora A, Delvin E, McCaddon A, Ahmadi KR, Harrington DJ. Vitamin B 12 status in health and disease: a critical review. Diagnosis of deficiency and insufficiency - clinical and laboratory pitfalls. Crit Rev Clin Lab Sci 2021; 58:399-429. [PMID: 33881359 DOI: 10.1080/10408363.2021.1885339] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Vitamin B12 (cobalamin) is an essential cofactor for two metabolic pathways. It is obtained principally from food of animal origin. Cobalamin becomes bioavailable through a series of steps pertaining to its release from dietary protein, intrinsic factor-mediated absorption, haptocorrin or transcobalamin-mediated transport, cellular uptake, and two enzymatic conversions (via methionine synthase and methylmalonyl-CoA-mutase) into cofactor forms: methylcobalamin and adenosylcobalamin. Vitamin B12 deficiency can masquerade as a multitude of illnesses, presenting different perspectives from the point of view of the hematologist, neurologist, gastroenterologist, general physician, or dietician. Increased physician vigilance and heightened patient awareness often account for its early presentation, and testing sometimes occurs during a phase of vitamin B12 insufficiency before the main onset of the disease. The chosen test often depends on its availability rather than on the diagnostic performance and sensitivity to irrelevant factors interfering with vitamin B12 markers. Although serum B12 is still the most commonly used and widely available test, diagnostics by holotranscobalamin, serum methylmalonic acid, and plasma homocysteine measurements have grown in the last several years in routine practice. The lack of a robust absorption test, coupled with compromised sensitivity and specificity of other tests (intrinsic factor and gastric parietal cell antibodies), hinders determination of the cause for depleted B12 status. This can lead to incorrect supplementation regimes and uncertainty regarding later treatment. This review discusses currently available knowledge on vitamin B12, informs the reader about the pitfalls of tests for assessing its deficiency, reviews B12 status in various populations at different disease stages, and provides recommendations for interpretation, treatment, and associated risks. Future directions for diagnostics of B12 status and health interventions are also discussed.
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Affiliation(s)
- Agata Sobczyńska-Malefora
- The Nutristasis Unit, Viapath, St. Thomas' Hospital, London, UK.,Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Edgard Delvin
- Sainte-Justine UHC Research Centre, Montreal, Canada.,Department of Biochemistry and Molecular Medicine, University of Montreal, Montreal, Canada
| | | | - Kourosh R Ahmadi
- Department of Nutrition & Metabolism, School of Biosciences and Medicine, University of Surrey, Guildford, UK
| | - Dominic J Harrington
- The Nutristasis Unit, Viapath, St. Thomas' Hospital, London, UK.,Faculty of Life Sciences and Medicine, King's College London, London, UK
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Bjune MS, Lindquist C, Hallvardsdotter Stafsnes M, Bjørndal B, Bruheim P, Aloysius TA, Nygård O, Skorve J, Madsen L, Dankel SN, Berge RK. Plasma 3-hydroxyisobutyrate (3-HIB) and methylmalonic acid (MMA) are markers of hepatic mitochondrial fatty acid oxidation in male Wistar rats. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:158887. [PMID: 33454435 DOI: 10.1016/j.bbalip.2021.158887] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/11/2021] [Accepted: 01/13/2021] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Discovery of specific markers that reflect altered hepatic fatty acid oxidation could help to detect an individual's risk of fatty liver, type 2 diabetes and cardiovascular disease at an early stage. Lipid and protein metabolism are intimately linked, but our understanding of this crosstalk remains limited. METHODS In male Wistar rats, we used synthetic fatty acid analogues (3-thia fatty acids) as a tool to induce hepatic fatty acid oxidation and mitochondrial biogenesis, to gain new insight into the link between fatty acid oxidation, amino acid metabolism and TCA cycle-related intermediate metabolites in liver and plasma. RESULTS Rats treated with 3-thia fatty acids had 3-fold higher hepatic, but not adipose and skeletal muscle, expression of the thioesterase 3-hydroxyisobutyryl-CoA hydrolase (Hibch), which controls the formation of 3-hydroxyisobutyrate (3-HIB) in the valine degradation pathway. Consequently, 3-thia fatty acid-stimulated hepatic fatty acid oxidation and ketogenesis was accompanied by decreased plasma 3-HIB and increased methylmalonic acid (MMA) concentrations further downstream in BCAA catabolism. The higher plasma MMA corresponded to higher MMA-CoA hydrolase activity and hepatic expression of GTP-specific succinyl-CoA synthase (Suclg2) and succinate dehydrogenase (Sdhb), and lower MMA-CoA mutase activity. Plasma 3-HIB correlated positively to plasma and hepatic concentrations of TAG, plasma total fatty acids, plasma NEFA and insulin/glucose ratio, while the reverse correlations were seen for MMA. CONCLUSION Our study provides new insight into TCA cycle-related metabolic changes associated with altered hepatic fatty acid flux, and identifies 3-HIB and MMA as novel circulating markers reflective of mitochondrial β-oxidation in male Wistar rats.
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Affiliation(s)
| | - Carine Lindquist
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Marit Hallvardsdotter Stafsnes
- Department of Biotechnology and Food Science, Faculty of Natural Sciences, NTNU Norwegian University of Science and Technology, N-7491 Trondheim, Norway
| | - Bodil Bjørndal
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Per Bruheim
- Department of Biotechnology and Food Science, Faculty of Natural Sciences, NTNU Norwegian University of Science and Technology, N-7491 Trondheim, Norway
| | - Thomas A Aloysius
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Ottar Nygård
- Department of Clinical Science, University of Bergen, Bergen, Norway; Department of Heart Disease, Haukeland University Hospital, Bergen, Norway
| | - Jon Skorve
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Lise Madsen
- Institute of Marine Research, NO-5817 Bergen, Norway
| | - Simon N Dankel
- Department of Clinical Science, University of Bergen, Bergen, Norway.
| | - Rolf Kristian Berge
- Department of Clinical Science, University of Bergen, Bergen, Norway; Department of Heart Disease, Haukeland University Hospital, Bergen, Norway.
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Urbanski G, Chabrun F, Ghali A, Lacombe V. Diagnosis of vitamin B12 deficiency: combined indicator of B12-status should be interpreted with caution in the case of renal impairment. Clin Chem Lab Med 2021; 59:e157-e159. [PMID: 33068380 DOI: 10.1515/cclm-2020-1245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 10/08/2020] [Indexed: 11/15/2022]
Affiliation(s)
- Geoffrey Urbanski
- Department of Internal Medicine, University Hospital, Angers, France
| | - Floris Chabrun
- Department of Biochemistry and Genetics, University Hospital, Angers, France
| | - Alaa Ghali
- Department of Internal Medicine, University Hospital, Angers, France
| | - Valentin Lacombe
- Department of Internal Medicine, University Hospital, Angers, France
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9
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Hinkel J, Schmitt J, Wurm M, Rosenbaum-Fabian S, Schwab KO, Jacobsen DW, Spiekerkoetter U, Fedosov SN, Hannibal L, Grünert SC. Elevated Plasma Vitamin B 12 in Patients with Hepatic Glycogen Storage Diseases. J Clin Med 2020; 9:jcm9082326. [PMID: 32707782 PMCID: PMC7463656 DOI: 10.3390/jcm9082326] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 07/13/2020] [Accepted: 07/17/2020] [Indexed: 12/14/2022] Open
Abstract
Background: Hepatic glycogen storage diseases (GSDs) are inborn errors of metabolism affecting the synthesis or breakdown of glycogen in the liver. This study, for the first time, systematically assessed vitamin B12 status in a large cohort of hepatic GSD patients. Methods: Plasma vitamin B12, total plasma homocysteine (tHcy) and methylmalonic acid concentrations were measured in 44 patients with hepatic GSDs and compared to 42 healthy age- and gender-matched controls. Correlations of vitamin B12 status with different disease markers of GSDs (including liver transaminase activities and triglycerides) as well as the vitamin B12 intake were studied. Results: GSD patients had significantly higher plasma vitamin B12 concentrations than healthy controls (p = 0.0002). Plasma vitamin B12 concentration remained elevated in GSD patients irrespective of vitamin B12 intake. Plasma vitamin B12 concentrations correlated negatively with triglyceride levels, whereas no correlations were detected with liver transaminase activities (GOT and GPT) in GSD patients. Merging biomarker data of healthy controls and GSD patients showed a positive correlation between vitamin B12 status and liver function, which suggests complex biomarker associations. A combined analysis of biomarkers permitted a reliable clustering of healthy controls versus GSD patients. Conclusions: Elevated plasma concentration of vitamin B12 (irrespective of B12 intake) is a common finding in patients with hepatic GSD. The negative correlation of plasma vitamin B12 with triglyceride levels suggests an influence of metabolic control on the vitamin B12 status of GSD patients. Elevated vitamin B12 was not correlated with GOT and GPT in our cohort of GSD patients. Merging of data from healthy controls and GSD patients yielded positive correlations between these biomarkers. This apparent dichotomy highlights the intrinsic complexity of biomarker associations and argues against generalizations of liver disease and elevated vitamin B12 in blood. Further studies are needed to determine whether the identified associations are causal or coincidental, and the possible impact of chronically elevated vitamin B12 on GSD.
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Affiliation(s)
- Julia Hinkel
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center—University of Freiburg, 79106 Freiburg, Germany; (J.H.); (J.S.); (S.R.-F.); (K.O.S.); (U.S.)
| | - Johannes Schmitt
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center—University of Freiburg, 79106 Freiburg, Germany; (J.H.); (J.S.); (S.R.-F.); (K.O.S.); (U.S.)
| | - Michael Wurm
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center—University of Freiburg, 79106 Freiburg, Germany; (J.H.); (J.S.); (S.R.-F.); (K.O.S.); (U.S.)
- Department of Pediatrics, St. Hedwigs Campus, University Children’s Hospital Regensburg, 93049 Regensburg, Germany;
| | - Stefanie Rosenbaum-Fabian
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center—University of Freiburg, 79106 Freiburg, Germany; (J.H.); (J.S.); (S.R.-F.); (K.O.S.); (U.S.)
| | - Karl Otfried Schwab
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center—University of Freiburg, 79106 Freiburg, Germany; (J.H.); (J.S.); (S.R.-F.); (K.O.S.); (U.S.)
| | - Donald W. Jacobsen
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA;
| | - Ute Spiekerkoetter
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center—University of Freiburg, 79106 Freiburg, Germany; (J.H.); (J.S.); (S.R.-F.); (K.O.S.); (U.S.)
| | - Sergey N. Fedosov
- Department of Molecular Biology and Genetics, Aarhus University, DK-8000 Aarhus C, Denmark;
| | - Luciana Hannibal
- Laboratory of Clinical Biochemistry and Metabolism, Department of General Pediatrics, Adolescent Medicine and Neonatology, Medical Center - University of Freiburg, Faculty of Medicine, 79106 Freiburg, Germany
- Correspondence: (L.H.); (S.C.G.)
| | - Sarah C. Grünert
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center—University of Freiburg, 79106 Freiburg, Germany; (J.H.); (J.S.); (S.R.-F.); (K.O.S.); (U.S.)
- Correspondence: (L.H.); (S.C.G.)
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Delvin E, Harrington DJ, Levy E. Undernutrition in childhood: Clinically based assessment tools and biological markers: Where are we and where should we go? Clin Nutr ESPEN 2019; 33:1-4. [PMID: 31451244 DOI: 10.1016/j.clnesp.2019.06.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 06/13/2019] [Indexed: 12/31/2022]
Abstract
Despite its association with poor clinical outcomes and increased hospital costs, as of today undernutrition still goes undetected in paediatric hospitals. The reported prevalence of undernutrition in paediatric patients varies considerably. This disparity is partly due to the diversity of methods for its detection and assessment, as well as to the lack of consensus regarding its definition. Several methods, based on varied combinations of morphology characteristics, estimated nutritional intakes and medical conditions have been developed during the last 25 years. However, these tools suffer from poor sensitivity and selectivity particularly in acute conditions. Also while having their own merit, these tools mainly view malnutrition from the energy standpoint, disregarding assessment of specific micronutrients such as minerals and vitamins. In this position paper we make the point that in the era of personalized medicine, present technology offers the possibility of going beyond the traditional nutritional tools for assessing patients' status, and propose the measurement of selected micronutrients and allied metabolic markers in nutritional workup schemes adapted to each clinical condition.
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Affiliation(s)
- E Delvin
- Sainte-Justine UHC Research Centre, Canada; Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Canada.
| | - D J Harrington
- Nutristasis Unit, Viapath, St Thomas Hospital, London, UK; Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - E Levy
- Sainte-Justine UHC Research Centre, Canada; Department of Nutrition, Université de Montréal, Montréal, Canada
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11
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A critical evaluation of results from genome-wide association studies of micronutrient status and their utility in the practice of precision nutrition. Br J Nutr 2019; 122:121-130. [DOI: 10.1017/s0007114519001119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
AbstractRapid advances in ‘omics’ technologies have paved the way forward to an era where more ‘precise’ approaches – ‘precision’ nutrition – which leverage data on genetic variability alongside the traditional indices, have been put forth as the state-of-the-art solution to redress the effects of malnutrition across the life course. We purport that this inference is premature and that it is imperative to first review and critique the existing evidence from large-scale epidemiological findings. We set out to provide a critical evaluation of findings from genome-wide association studies (GWAS) in the roadmap to precision nutrition, focusing on GWAS of micronutrient disposition. We found that a large number of loci associated with biomarkers of micronutrient status have been identified. Mean estimates of heritability of micronutrient status ranged between 20 and 35 % for minerals, 56–59 % for water-soluble and 30–70 % for fat-soluble vitamins. With some exceptions, the majority of the identified genetic variants explained little of the overall variance in status for each micronutrient, ranging between 1·3 and 8 % (minerals), <0·1–12 % (water-soluble) and 1·7–2·3 % for (fat-soluble) vitamins. However, GWAS have provided some novel insight into mechanisms that underpin variability in micronutrient status. Our findings highlight obvious gaps that need to be addressed if the full scope of precision nutrition is ever to be realised, including research aimed at (i) dissecting the genetic basis of micronutrient deficiencies or ‘response’ to intake/supplementation (ii) identifying trans-ethnic and ethnic-specific effects (iii) identifying gene–nutrient interactions for the purpose of unravelling molecular ‘behaviour’ in a range of environmental contexts.
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