C3-epimerization of 25-hydroxyvitamin D increases with increasing serum 25-hydroxyvitamin D levels and shows a high degree of tracking over time
| dc.contributor.author | Kubiak, Julia M. | |
| dc.contributor.author | Grimnes, Guri | |
| dc.contributor.author | Cashman, Kevin D. | |
| dc.contributor.author | Kamycheva, Elena | |
| dc.contributor.author | Dowling, Kirsten G. | |
| dc.contributor.author | Skrabáková, Zuzana | |
| dc.contributor.author | Jorde, Rolf | |
| dc.contributor.funder | Seventh Framework Programme | en |
| dc.contributor.funder | Helse Nord RHF | en |
| dc.contributor.funder | Universitetet i Tromsø | en |
| dc.contributor.funder | Novo Nordisk | en |
| dc.contributor.funder | Norges Forskningsråd | en |
| dc.contributor.funder | Norske Kvinners Sanitetsforening | en |
| dc.date.accessioned | 2018-02-26T16:09:32Z | |
| dc.date.available | 2018-02-26T16:09:32Z | |
| dc.date.issued | 2018-02-21 | |
| dc.date.updated | 2018-02-26T15:55:37Z | |
| dc.description.abstract | Objective: Evaluate the effects of serum 25-hydroxyvitamin D (25(OH)D) levels, vitamin D binding protein (DBP) and genetic factors on C3-epimerization of 25(OH)D and follow the tracking of the epimer during one year. Design: Cross-sectional and longitudinal study. Methods: Data from eight previously conducted, Tromsø based studies (3 observational, 5 randomized controlled trials) were combined. 25(OH)D serum samples were re-analyzed with a LC-MS/MS method that also resolves and measures the metabolite C3-epi-25(OH)D3. Data on vitamin D binding protein (DBP) phenotype (based on single nucleotide polymorphisms (SNPs) rs4588 and rs7041) and genetic determinants for serum 25(OH)D (SNPs rs2282679, rs10741657, rs3829251 and rs6013897) were collected where available. Results: 2219 subjects were included. Median (5th, 95th percentiles) baseline serum values of 25(OH)D3, C3-epi-25(OH)D3, and %-C3-epi-25(OH)D3 were 49.1 (22.1, 92.8) nmol/L, 2.3 (0.9, 6.0) nmol/L and 4.4 (2.7, 8.4) %, respectively. The highest baseline values were 230.5 nmol/L for 25(OH)D3, 79.7 nmol/L for C3-epi-25(OH)D3 and 48.2% for %-C3-epi-25(OH)D3. There was a strong correlation between serum 25(OH)D3 and C3-epi-25(OH)D3. The %-C3-epi-25(OH)D3 value increased with increasing serum 25(OH)D3, but leveled off at ~7% at a 25(OH)D3 concentration of ~120–140 nmol/L. There was a significant degree of tracking for %-C3-epi-25(OH)D3 (correlation coefficient rho between baseline and 1-year values 0.39, P < 0.001). The %-C3-epi-25(OH)D3 level was not related to serum DBP level, DBP phenotype nor to SNPs related to serum 25(OH)D3 level. The serum 25(OH)D3 level could explain less than 3% of %-C3-epi-25(OH)D3 variation. Conclusions: There are considerable individual and reproducible differences in percent C3-epimerization of uncertain clinical importance. | en |
| dc.description.status | Peer reviewed | en |
| dc.description.version | Accepted Version | en |
| dc.format.mimetype | application/pdf | en |
| dc.identifier.citation | Kubiak, J. M., Grimnes, G., Cashman, K. D., Kamycheva, E., Dowling, K., Skrabáková, Z. and Jorde, R. 'C3-epimerization of 25-hydroxyvitamin D increases with increasing serum 25-hydroxyvitamin D levels and shows a high degree of tracking over time', Clinical Biochemistry, 54, pp. 61-67. doi: 10.1016/j.clinbiochem.2018.02.013 | en |
| dc.identifier.doi | 10.1016/j.clinbiochem.2018.02.013 | |
| dc.identifier.endpage | 67 | en |
| dc.identifier.issn | 0009-9120 | |
| dc.identifier.journaltitle | Clinical biochemistry | en |
| dc.identifier.startpage | 61 | en |
| dc.identifier.uri | https://hdl.handle.net/10468/5547 | |
| dc.identifier.volume | 54 | |
| dc.language.iso | en | en |
| dc.publisher | Elsevier | en |
| dc.relation.project | info:eu-repo/grantAgreement/EC/FP7::SP1::KBBE/613977/EU/Food-based solutions for Optimal vitamin D Nutrition and health through the life cycle/ODIN | en |
| dc.relation.uri | https://www.sciencedirect.com/science/article/pii/S0009912017311980 | |
| dc.rights | © 2018 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved. This manuscript version is made available under the CC-BY-NC-ND 4.0 license. | en |
| dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/4.0/ | en |
| dc.subject | Vitamin D | en |
| dc.subject | Epimerization effects | en |
| dc.subject | Vitamin D binding protein (DBP) | en |
| dc.subject | Calcium metabolism | en |
| dc.title | C3-epimerization of 25-hydroxyvitamin D increases with increasing serum 25-hydroxyvitamin D levels and shows a high degree of tracking over time | en |
| dc.type | Article (peer-reviewed) | en |
