Vitamin D metabolism and regulation in pediatric MSCs

• Published in: The Journal of steroid biochemistry and molecular biology Vol. 164; pp. 287 - 291
• Main Authors: Ruggiero, B., Padwa, B.L., Christoph, K.M., Zhou, S., Glowacki, J.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.11.2016; Elsevier BV
• Subjects: 17β-Estradiol; 1α-Hydroxylase; 25-Hydroxyvitamin D3 1-alpha-Hydroxylase - genetics; 25-Hydroxyvitamin D3 1-alpha-Hydroxylase - metabolism; Adults; Autocrine signalling; Bone marrow; Bone Marrow Cells - cytology; Bone Marrow Cells - drug effects; Bone Marrow Cells - metabolism; Bone turnover; Calcifediol - metabolism; Calcifediol - pharmacology; Cell Differentiation - drug effects; Child; Children; Cholestanetriol 26-Monooxygenase - genetics; Cholestanetriol 26-Monooxygenase - metabolism; Cytochrome P450 Family 2 - genetics; Cytochrome P450 Family 2 - metabolism; Enzyme-linked immunosorbent assay; Estrogen Receptor alpha - genetics; Estrogen Receptor alpha - metabolism; Estrogen receptors; Extra-renal; Female; Gene expression; Gene Expression Regulation - drug effects; Homeostasis; Humans; Hydroxylase; Hydroxylation; Low Density Lipoprotein Receptor-Related Protein-2 - genetics; Low Density Lipoprotein Receptor-Related Protein-2 - metabolism; Male; Marrow stromal cells; Mesenchymal Stem Cells - cytology; Mesenchymal Stem Cells - drug effects; Mesenchymal Stem Cells - metabolism; Metabolism; Osteoblastogenesis; Osteoblasts; Osteoblasts - cytology; Osteoblasts - drug effects; Osteoblasts - metabolism; Paracrine signalling; Polymerase chain reaction; Primary Cell Culture; Receptors, Calcitriol - genetics; Receptors, Calcitriol - metabolism; Sex differences; Sex Factors; Stromal cells; Vitamin D; Vitamin D receptors; Vitamin D3 24-Hydroxylase - genetics; Vitamin D3 24-Hydroxylase - metabolism; hMSC; PTH; VDR; Marrow stromal cells; 1α,25(OH)2D; ER; DBP; Vitamin D; 25(OH)D; CYP; Children; 1α-Hydroxylase; FGF23; BMI; Extra-renal
• ISSN: 0960-0760; 1879-1220
• DOI: 10.1016/j.jsbmb.2015.09.025

•Pediatric MSCs showed constitutive expression of CYP27B1 and other vitamin D-related genes.•There was greater expression of vitamin D-related genes in MSCs from boys than girls.•Those gender differences had not been seen in MSCs from adults.•Vitamin D-related genes were upregulated by in vitro treatment with 25(OH)D3 and with 17β-estradiol.•Expression and regulation of vitamin D-related genes in pediatric hMSCs reinforces an autocrine/paracrine role for vitamin D in hMSCs. Vitamin D is crucial for mineral homeostasis and contributes to bone metabolism by inducing osteoblast differentiation of marrow stromal cells (MSCs). We recently reported that MSCs from adults demonstrate 1α-hydroxylase activity in vitro and express vitamin D-related genes; this raises a possible autocrine/paracrine role for D activation in pre-osteoblasts. In this studies, we tested the hypotheses that pediatric MSCs have 1α-hydroxylase activity and express vitamin D-related genes. With IRB approval, we isolated MSCs from discarded excess iliac marrow graft from 6 male and 6 female subjects (age 8–12 years) undergoing alveolar cleft repair. 1α-hydroxylation of substrate 25(OH)D3 was measured by ELISA for 1α,25(OH)2D. RT-PCR was used for gene expression. Pediatric MSCs showed a range of 1α-hydroxylase activity in vitro. There was constitutive expression of vitamin D receptor (VDR), megalin, d-hydroxylases (CYP27B1, CYP27A1, CYP2R1, and CYP24A1), and estrogen receptor (ER). There was 2.6-fold greater expression of CYP27B1 and 3.5-fold greater expression of CYP24A1 in MSCs from boys compared with girls. There was 2.4-fold greater expression of ERα and 3.2-fold greater expression of megalin in MSCs from boys. In preliminary studies, treatment of female pediatric MSCs with 10nM 17β-estradiol resulted in upregulation of CYP27B1 and CYP24A1, as well as VDR, megalin, ERα, and ERβ. Treatment with 25(OH)D3 upregulated CYP27B1, VDR, and ERα. Expression and regulation of vitamin D related genes in pediatric hMSCs reinforces an autocrine/paracrine role for vitamin D in hMSCs. Finding striking gender differences in MSCs from children was not seen with MSCs from adults and adds insight to the metabolic environment of bone and presents a research approach for investigating and optimizing pediatric bone health.