Is a well-known down-regulated primary target of vitamin D and its receptor, while PTH protein signaling upregulates CYP27B1 gene expression [36,37]. This inverse correlation between vitamin D and PTH concentrations is of major importance for appropriate bone mineralization [38]. In this study, we could confirm this inverse correlation, when plotting the relative change of PTH concentrations against the change of the serum 25(OH)D3 concentrations (R2 = 0.231, p = 0.00002; Fig. S1 in File S1). This indicates that the overall vitamin D responsiveness of the 71 participants 15481974 target=’resource_window’>10457188 of the study is according to expectations. Since the PTH gene is exclusively expressed in the parathyroid gland, i.e. in a tissue, which is not easily available for biopsies, it is not an appropriate choice for vitamin D gene expression studies. Therefore, we screened for more globally expressed primary VDR target genes. Our transcriptome- and genome-wide studies in THP-1 monocytes [21,39] suggested the genes CD14 and THBD to be well suited. In contrast to many other primary VDR target genes, CD14 and THBD are known for their prominent, longlasting response to treatment with 1,25(OH)2D3. Moreover, both genes are regulated by a strong VDR binding site, which for CD14 is conserved between VDR ChIP-seq datasets of monocytes and colon cells (Fig. S2A in File S1) and for THBD even between monocytes, lymphoblastoids and colon cells (Fig. S2B in File S1). Interestingly, in a very recent study the same two genes were foundTable 1. Main clinical and biochemical characteristics of the VitDmet study participants at baseline and their changes during the study.Parameter Serum [25(OH)D3] start (nM) Delta serum [25(OH)D3] (nM) BMI start (kg/m2) Delta BMI (kg/m2) Serum [PTH] start (pg/ml) Delta serum [PTH] (pg/ml) Serum [Ca] start (mM) Delta serum [Ca] (mM) Age (years) Gender (female/male)Title Loaded From File Placebo group*, n = 22** 58.9+/210.2 1.1 (24.7; 6.9) 30.2+/22.8 0.23 (20.12; 0.58) 44.6+/218.2 4.7 (1.4; 8.0) 2.35+/20.09 20.06 (20.09; 20.03) 67.4+/25.7 3 (13.6 )/19 (86.4 )40 mg vitamin D3/day group, n = 25 80 mg vitamin D3/day group, n = 24 59.0+/27.6 26.7 (20.0; 33.4) 28.8+/22.7 0.34 (0.13; 0.55) 41.5+/29.5 20.5 (23.5; 2.5) 2.31+/20.05 20.04 (20.07; 20.01) 66.2+/25.5 4 (16 )/21 (84 ) 57.8+/210.3 44.8 (36.2; 53.4) 29.5+/23.0 0.33 (0.07; 0.53) 43.8+/211.1 23.7 (26.1; 21.3) 2.33+/20.08 20.03 (20.06; 0.00) 66.4+/24.3 3 (12 )/21 (88 )*all participants were asked to keep their diet and other lifestyle habits unchanged during the study and were allowed to take up to 20 mg vitamin D3/day. **random assignment of the participants to the three groups. Means and standard deviations for the baseline characteristics before intervention or mean parameter change with 95 confidence interval after the intervention are indicated for the three arms of the study. The detailed data of all 71 study participants are shown in Table S2 in File S2. doi:10.1371/journal.pone.0071042.tCD14 and THBD as Transcriptomic Markers in VitDmetin a comparison of a larger number of vitamin D transcriptomics studies (including our own) to be most significantly correlated with serum 25(OH)D3 concentrations of the Norwegian Women and Cancer Post-genome cohort [40]. Accordingly, we found that the relative mRNA expression of CD14 and THBD in PBMCs (normalized by three housekeeping genes) isolated from the 71 participants at the start of the study correlated highly significantly with the Title Loaded From File respective expression in cells taken at the end of the.Is a well-known down-regulated primary target of vitamin D and its receptor, while PTH protein signaling upregulates CYP27B1 gene expression [36,37]. This inverse correlation between vitamin D and PTH concentrations is of major importance for appropriate bone mineralization [38]. In this study, we could confirm this inverse correlation, when plotting the relative change of PTH concentrations against the change of the serum 25(OH)D3 concentrations (R2 = 0.231, p = 0.00002; Fig. S1 in File S1). This indicates that the overall vitamin D responsiveness of the 71 participants 15481974 target=’resource_window’>10457188 of the study is according to expectations. Since the PTH gene is exclusively expressed in the parathyroid gland, i.e. in a tissue, which is not easily available for biopsies, it is not an appropriate choice for vitamin D gene expression studies. Therefore, we screened for more globally expressed primary VDR target genes. Our transcriptome- and genome-wide studies in THP-1 monocytes [21,39] suggested the genes CD14 and THBD to be well suited. In contrast to many other primary VDR target genes, CD14 and THBD are known for their prominent, longlasting response to treatment with 1,25(OH)2D3. Moreover, both genes are regulated by a strong VDR binding site, which for CD14 is conserved between VDR ChIP-seq datasets of monocytes and colon cells (Fig. S2A in File S1) and for THBD even between monocytes, lymphoblastoids and colon cells (Fig. S2B in File S1). Interestingly, in a very recent study the same two genes were foundTable 1. Main clinical and biochemical characteristics of the VitDmet study participants at baseline and their changes during the study.Parameter Serum [25(OH)D3] start (nM) Delta serum [25(OH)D3] (nM) BMI start (kg/m2) Delta BMI (kg/m2) Serum [PTH] start (pg/ml) Delta serum [PTH] (pg/ml) Serum [Ca] start (mM) Delta serum [Ca] (mM) Age (years) Gender (female/male)Placebo group*, n = 22** 58.9+/210.2 1.1 (24.7; 6.9) 30.2+/22.8 0.23 (20.12; 0.58) 44.6+/218.2 4.7 (1.4; 8.0) 2.35+/20.09 20.06 (20.09; 20.03) 67.4+/25.7 3 (13.6 )/19 (86.4 )40 mg vitamin D3/day group, n = 25 80 mg vitamin D3/day group, n = 24 59.0+/27.6 26.7 (20.0; 33.4) 28.8+/22.7 0.34 (0.13; 0.55) 41.5+/29.5 20.5 (23.5; 2.5) 2.31+/20.05 20.04 (20.07; 20.01) 66.2+/25.5 4 (16 )/21 (84 ) 57.8+/210.3 44.8 (36.2; 53.4) 29.5+/23.0 0.33 (0.07; 0.53) 43.8+/211.1 23.7 (26.1; 21.3) 2.33+/20.08 20.03 (20.06; 0.00) 66.4+/24.3 3 (12 )/21 (88 )*all participants were asked to keep their diet and other lifestyle habits unchanged during the study and were allowed to take up to 20 mg vitamin D3/day. **random assignment of the participants to the three groups. Means and standard deviations for the baseline characteristics before intervention or mean parameter change with 95 confidence interval after the intervention are indicated for the three arms of the study. The detailed data of all 71 study participants are shown in Table S2 in File S2. doi:10.1371/journal.pone.0071042.tCD14 and THBD as Transcriptomic Markers in VitDmetin a comparison of a larger number of vitamin D transcriptomics studies (including our own) to be most significantly correlated with serum 25(OH)D3 concentrations of the Norwegian Women and Cancer Post-genome cohort [40]. Accordingly, we found that the relative mRNA expression of CD14 and THBD in PBMCs (normalized by three housekeeping genes) isolated from the 71 participants at the start of the study correlated highly significantly with the respective expression in cells taken at the end of the.
