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Mata-Greenwood E, Chow WL, Anti NAO, Sands LD, Adeoye O, Ford SP, Nathanielsz PW. Dysregulation of Glucocorticoid Receptor Homeostasis and Glucocorticoid-Associated Genes in Umbilical Cord Endothelial Cells of Diet-Induced Obese Pregnant Sheep. Int J Mol Sci 2024; 25:2311. [PMID: 38396987 PMCID: PMC10888705 DOI: 10.3390/ijms25042311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 02/08/2024] [Accepted: 02/10/2024] [Indexed: 02/25/2024] Open
Abstract
Maternal obesity (MO) is associated with offspring cardiometabolic diseases that are hypothesized to be partly mediated by glucocorticoids. Therefore, we aimed to study fetal endothelial glucocorticoid sensitivity in an ovine model of MO. Rambouillet/Columbia ewes were fed either 100% (control) or 150% (MO) National Research Council recommendations from 60 d before mating until near-term (135 days gestation). Sheep umbilical vein and artery endothelial cells (ShUVECs and ShUAECs) were used to study glucocorticoid receptor (GR) expression and function in vitro. Dexamethasone dose-response studies of gene expression, activation of a glucocorticoid response element (GRE)-dependent luciferase reporter vector, and cytosolic/nuclear GR translocation were used to assess GR homeostasis. MO significantly increased basal GR protein levels in both ShUVECs and ShUAECs. Increased GR protein levels did not result in increased dexamethasone sensitivity in the regulation of key endothelial gene expression such as endothelial nitric oxide synthase, plasminogen activator inhibitor 1, vascular endothelial growth factor, or intercellular adhesion molecule 1. In ShUVECs, MO increased GRE-dependent transactivation and FKBP prolyl isomerase 5 (FKBP5) expression. ShUAECs showed generalized glucocorticoid resistance in both dietary groups. Finally, we found that ShUVECs were less sensitive to dexamethasone-induced activation of GR than human umbilical vein endothelial cells (HUVECs). These findings suggest that MO-mediated effects in the offspring endothelium could be further mediated by dysregulation of GR homeostasis in humans as compared with sheep.
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Affiliation(s)
- Eugenia Mata-Greenwood
- Lawrence D. Longo Center for Perinatal Biology, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA; (W.L.C.); (N.A.O.A.); (L.D.S.)
| | - Wendy L. Chow
- Lawrence D. Longo Center for Perinatal Biology, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA; (W.L.C.); (N.A.O.A.); (L.D.S.)
| | - Nana A. O. Anti
- Lawrence D. Longo Center for Perinatal Biology, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA; (W.L.C.); (N.A.O.A.); (L.D.S.)
| | - LeeAnna D. Sands
- Lawrence D. Longo Center for Perinatal Biology, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA; (W.L.C.); (N.A.O.A.); (L.D.S.)
| | - Olayemi Adeoye
- Department of Pharmaceutical Sciences, School of Pharmacy, Loma Linda University, Loma Linda, CA 92350, USA;
| | - Stephen P. Ford
- Center for the Study of Fetal Programming, Department of Animal Science, University of Wyoming, Laramie, WY 82071, USA (P.W.N.)
| | - Peter W. Nathanielsz
- Center for the Study of Fetal Programming, Department of Animal Science, University of Wyoming, Laramie, WY 82071, USA (P.W.N.)
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2
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Mata-Greenwood E, Westenburg HCA, Zamudio S, Illsley NP, Zhang L. Decreased Vitamin D Levels and Altered Placental Vitamin D Gene Expression at High Altitude: Role of Genetic Ancestry. Int J Mol Sci 2023; 24:3389. [PMID: 36834800 PMCID: PMC9967090 DOI: 10.3390/ijms24043389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/14/2023] [Accepted: 01/24/2023] [Indexed: 02/10/2023] Open
Abstract
High-altitude hypoxia challenges reproduction; particularly in non-native populations. Although high-altitude residence is associated with vitamin D deficiency, the homeostasis and metabolism of vitamin D in natives and migrants remain unknown. We report that high altitude (3600 m residence) negatively impacted vitamin D levels, with the high-altitude Andeans having the lowest 25-OH-D levels and the high-altitude Europeans having the lowest 1α,25-(OH)2-D levels. There was a significant interaction of genetic ancestry with altitude in the ratio of 1α,25-(OH)2-D to 25-OH-D; with the ratio being significantly lower in Europeans compared to Andeans living at high altitude. Placental gene expression accounted for as much as 50% of circulating vitamin D levels, with CYP2R1 (25-hydroxylase), CYP27B1 (1α-hydroxylase), CYP24A1 (24-hydroxylase), and LRP2 (megalin) as the major determinants of vitamin D levels. High-altitude residents had a greater correlation between circulating vitamin D levels and placental gene expression than low-altitude residents. Placental 7-dehydrocholesterol reductase and vitamin D receptor were upregulated at high altitude in both genetic-ancestry groups, while megalin and 24-hydroxylase were upregulated only in Europeans. Given that vitamin D deficiency and decreased 1α,25-(OH)2-D to 25-OH-D ratios are associated with pregnancy complications, our data support a role for high-altitude-induced vitamin D dysregulation impacting reproductive outcomes, particularly in migrants.
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Affiliation(s)
- Eugenia Mata-Greenwood
- Lawrence D. Longo Center for Perinatal Biology, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
| | - Hans C. A. Westenburg
- Lawrence D. Longo Center for Perinatal Biology, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
| | - Stacy Zamudio
- Placental Research Group LLC, Maplewood, NJ 07040, USA
| | | | - Lubo Zhang
- Lawrence D. Longo Center for Perinatal Biology, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
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Chen X, An Z, Wei L, Zhang J, Li J, Wang Z, Gao C, Wei D. Vitamin D 3 Metabolic Enzymes in Plateau Zokor ( Myospalax baileyi) and Plateau Pika ( Ochotona curzoniae): Expression and Response to Hypoxia. Animals (Basel) 2022; 12:ani12182371. [PMID: 36139230 PMCID: PMC9495108 DOI: 10.3390/ani12182371] [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: 08/03/2022] [Revised: 09/02/2022] [Accepted: 09/06/2022] [Indexed: 11/16/2022] Open
Abstract
Vitamin D3 (D3) is produced endogenously from 7-dehydrocholesterol by irradiation and is an important secosteroid for the absorption of calcium and phosphate. Lithocholic acid (LCA) increases intestinal paracellular calcium absorption in a vitamin D receptor-dependent manner in vitamin D-deficient rats. The plateau zokor (Myospalax baileyi), a strictly subterranean species, and plateau pika are endemic to the Qinghai-Tibet Plateau. To verify whether the zokors were deficient in D3 and reveal the effects of hypoxia on D3 metabolism in the zokors and pikas, we measured the levels of 25(OH)D3, calcium, and LCA, and quantified the expression levels of D3 metabolism-related genes. The results showed an undetectable serum level of 25(OH)D3 and a significantly higher concentration of LCA in the serum of plateau zokor, but its calcium concentration was within the normal range compared with that of plateau pika and Sprague-Dawley rats. With increasing altitude, the serum 25(OH)D3 levels in plateau pika decreased significantly, and the mRNA and protein levels of CYP2R1 (in the liver) and CYP27B1 (in the kidney) in plateau pika decreased significantly. Our results indicate that plateau zokors were deficient in D3 and abundant in LCA, which might be a substitution of D3 in the zokor. Furthermore, hypoxia suppresses the metabolism of D3 by down-regulating the expression of CYP2R1 and CYP27B1 in plateau pika.
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Affiliation(s)
- Xiaoqi Chen
- Research Center for High Altitude Medicine, Qinghai University, Xining 810016, China
- State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China
| | - Zhifang An
- State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China
| | - Linna Wei
- State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China
| | - Jiayu Zhang
- State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China
| | - Jimei Li
- Research Center for High Altitude Medicine, Qinghai University, Xining 810016, China
- State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China
| | - Zhijie Wang
- Research Center for High Altitude Medicine, Qinghai University, Xining 810016, China
- State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China
| | - Conghui Gao
- State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China
| | - Dengbang Wei
- Research Center for High Altitude Medicine, Qinghai University, Xining 810016, China
- State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China
- Correspondence: ; Tel.: +86-971-531-0695
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Sparks AM, Johnston SE, Handel I, Pilkington JG, Berry J, Pemberton JM, Nussey DH, Mellanby RJ. Vitamin D status is heritable and under environment-dependent selection in the wild. Mol Ecol 2022; 31:4607-4621. [PMID: 34888965 PMCID: PMC9545857 DOI: 10.1111/mec.16318] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 11/12/2021] [Accepted: 11/24/2021] [Indexed: 11/30/2022]
Abstract
Vitamin D has a well-established role in skeletal health and is increasingly linked to chronic disease and mortality in humans and companion animals. Despite the clear significance of vitamin D for health and obvious implications for fitness under natural conditions, no longitudinal study has tested whether the circulating concentration of vitamin D is under natural selection in the wild. Here, we show that concentrations of dietary-derived vitamin D2 and endogenously produced vitamin D3 metabolites are heritable and largely polygenic in a wild population of Soay sheep (Ovis aries). Vitamin D2 status was positively associated with female adult survival, and vitamin D3 status predicted female fecundity in particular, good environment years when sheep density and competition for resources was low. Our study provides evidence that vitamin D status has the potential to respond to selection, and also provides new insights into how vitamin D metabolism is associated with fitness in the wild.
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Affiliation(s)
- Alexandra M. Sparks
- Institute of Evolutionary BiologySchool of Biological SciencesUniversity of EdinburghEdinburghUK
- Faculty of Biological SciencesSchool of BiologyUniversity of LeedsLeedsUK
| | - Susan E. Johnston
- Institute of Evolutionary BiologySchool of Biological SciencesUniversity of EdinburghEdinburghUK
| | - Ian Handel
- Royal (Dick) School of Veterinary Studies and The Roslin InstituteThe University of EdinburghHospital for Small AnimalsRoslinUK
| | - Jill G. Pilkington
- Institute of Evolutionary BiologySchool of Biological SciencesUniversity of EdinburghEdinburghUK
| | - Jacqueline Berry
- Specialist Assay Laboratory (Vitamin D)Clinical BiochemistryManchester Royal InfirmaryManchesterUK
| | - Josephine M. Pemberton
- Institute of Evolutionary BiologySchool of Biological SciencesUniversity of EdinburghEdinburghUK
| | - Daniel H. Nussey
- Institute of Evolutionary BiologySchool of Biological SciencesUniversity of EdinburghEdinburghUK
| | - Richard J. Mellanby
- Royal (Dick) School of Veterinary Studies and The Roslin InstituteThe University of EdinburghHospital for Small AnimalsRoslinUK
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Chen Z, Wang C, Blood A, Bragg S, Mata-Greenwood E. Renal functional, transcriptome, and methylome adaptations in pregnant Sprague Dawley and Brown Norway rats. PLoS One 2022; 17:e0269792. [PMID: 35709218 PMCID: PMC9202892 DOI: 10.1371/journal.pone.0269792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 05/30/2022] [Indexed: 11/19/2022] Open
Abstract
Pregnancy induces maternal renal adaptations that include increased glomerular filtration rate and renal blood flow which can be compromised in obstetrical complications such as preeclampsia. Brown Norway (BN) rat pregnancies are characterized by placental insufficiency, maternal hypertension, and proteinuria. We hypothesized that BN pregnancies would show renal functional, anatomical, or molecular features of preeclampsia. We used the Sprague-Dawley (CD) rat as a model of normal pregnancy. Pregnancy increased the glomerular filtration rate by 50% in CD rats and 12.2% in BN rats compared to non-pregnancy, and induced proteinuria only in BN rats. BN pregnancies showed a decrease in maternal plasma calcitriol levels, which correlated with renal downregulation of 1-alpha hydroxylase and upregulation of 24-hydroxylase. RNA sequencing revealed that pregnancy induced 297 differentially expressed genes (DEGs) in CD rats and 174 DEGs in BN rats, indicating a 70% increased response to pregnancy in CD compared to BN rats. Pregnancy induced activation of innate immune pathways such as ‘Role of Pattern Recognition Receptors’, and ‘Interferon signaling’ with interferon regulatory factor 7 as a common upregulated upstream factor in both rat strains. Comparison of rat strain transcriptomic profiles revealed 475 DEGs at non-pregnancy and 569 DEGs at pregnancy with 205 DEGs shared at non-pregnancy (36%), indicating that pregnancy interacted with rat strain in regulating 64% of the DEGs. Pathway analysis revealed that pregnancy induced a switch in renal transcriptomics in BN rats from ‘inhibition of renal damage’ to ‘acute phase reaction’, ‘recruitment of immune cells’ and ‘inhibition of 1,25-(OH)2-vitamin D synthesis’. Key upstream regulators included peroxisome-proliferator-activated receptor alpha (PPARA), platelet-derived growth factor B dimer (PDGF-BB), and NF-kB p65 (RELA). DNA methylome profiling by reduced representation bisulfite sequencing studies revealed that the DEGs did not correlate with changes in promoter methylation. In sum, BN rat kidneys respond to pregnancy-specific signals with an increase in pro-inflammatory gene networks and alteration of metabolic pathways including vitamin D deficiency in association with mild proteinuria and blunted GFR increase. However, the lack of glomerular endotheliosis and mild hypertension/proteinuria in pregnant BN rats limits the relevance of this rat strain for preeclampsia research.
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Affiliation(s)
- Zhong Chen
- Center for Genomics, School of Medicine, Loma Linda University, Loma Linda, CA, United States of America
| | - Charles Wang
- Center for Genomics, School of Medicine, Loma Linda University, Loma Linda, CA, United States of America
| | - Arlin Blood
- Lawrence D. Longo Center for Perinatal Biology, School of Medicine, Loma Linda University, Loma Linda, CA, United States of America
| | - Shannon Bragg
- Lawrence D. Longo Center for Perinatal Biology, School of Medicine, Loma Linda University, Loma Linda, CA, United States of America
| | - Eugenia Mata-Greenwood
- Department of Pediatrics, School of Medicine, Loma Linda University, Loma Linda, CA, United States of America
- * E-mail:
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Layton KKS, Bradbury IR. Harnessing the power of multi-omics data for predicting climate change response. J Anim Ecol 2021; 91:1064-1072. [PMID: 34679193 DOI: 10.1111/1365-2656.13619] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 10/11/2021] [Indexed: 01/19/2023]
Abstract
Predicting how species will respond to future climate change is of central importance in the midst of the global biodiversity crisis, and recent work has demonstrated the utility of population genomics for improving these predictions. Here, we suggest a broadening of the approach to include other types of genomic variants that play an important role in adaptation, like structural (e.g. copy number variants) and epigenetic variants (e.g. DNA methylation). These data could provide additional power for forecasting response, especially in weakly structured or panmictic species. Incorporating structural and epigenetic variation into estimates of climate change vulnerability, or maladaptation, may not only improve prediction power but also provide insight into the molecular mechanisms underpinning species' response to climate change.
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Affiliation(s)
- Kara K S Layton
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| | - Ian R Bradbury
- Northwest Atlantic Fisheries Centre, Fisheries and Oceans Canada, St. John's, Canada
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Hurst EA, Homer NZ, Mellanby RJ. Vitamin D Metabolism and Profiling in Veterinary Species. Metabolites 2020; 10:E371. [PMID: 32942601 PMCID: PMC7569877 DOI: 10.3390/metabo10090371] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/11/2020] [Accepted: 09/13/2020] [Indexed: 12/17/2022] Open
Abstract
The demand for vitamin D analysis in veterinary species is increasing with the growing knowledge of the extra-skeletal role vitamin D plays in health and disease. The circulating 25-hydroxyvitamin-D (25(OH)D) metabolite is used to assess vitamin D status, and the benefits of analysing other metabolites in the complex vitamin D pathway are being discovered in humans. Profiling of the vitamin D pathway by liquid chromatography tandem mass spectrometry (LC-MS/MS) facilitates simultaneous analysis of multiple metabolites in a single sample and over wide dynamic ranges, and this method is now considered the gold-standard for quantifying vitamin D metabolites. However, very few studies report using LC-MS/MS for the analysis of vitamin D metabolites in veterinary species. Given the complexity of the vitamin D pathway and the similarities in the roles of vitamin D in health and disease between humans and companion animals, there is a clear need to establish a comprehensive, reliable method for veterinary analysis that is comparable to that used in human clinical practice. In this review, we highlight the differences in vitamin D metabolism between veterinary species and the benefits of measuring vitamin D metabolites beyond 25(OH)D. Finally, we discuss the analytical challenges in profiling vitamin D in veterinary species with a focus on LC-MS/MS methods.
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Affiliation(s)
- Emma A. Hurst
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush, Midlothian, Edinburgh, Scotland EH25 9RG, UK;
- Mass Spectrometry Core, Edinburgh Clinical Research Facility, Queen’s Medical Research Institute, The University of Edinburgh, Little France Crescent, Edinburgh, Scotland EH16 4TJ, UK;
| | - Natalie Z. Homer
- Mass Spectrometry Core, Edinburgh Clinical Research Facility, Queen’s Medical Research Institute, The University of Edinburgh, Little France Crescent, Edinburgh, Scotland EH16 4TJ, UK;
| | - Richard J. Mellanby
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush, Midlothian, Edinburgh, Scotland EH25 9RG, UK;
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Wilkens MR, Firmenich CS, Schnepel N, Muscher-Banse AS. A reduced protein diet modulates enzymes of vitamin D and cholesterol metabolism in young ruminants. J Steroid Biochem Mol Biol 2019; 186:196-202. [PMID: 30394334 DOI: 10.1016/j.jsbmb.2018.10.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 10/16/2018] [Accepted: 10/24/2018] [Indexed: 12/19/2022]
Abstract
Besides other adverse effects, a low protein diet has been shown to modulate cholesterol and vitamin D metabolism in monogastric species like rats and humans. As ruminants can increase the efficiency of the rumino-hepatic circulation of urea, it is assumed that goats should be able to compensate for a low dietary protein intake better. After a dietary protein restriction (9% vs. 20%) for six weeks, plasma concentrations of urea, albumin, 1,25-dihydroxyvitamin D3 and calcium were decreased, while plasma 25-hydroxyvitamin D3 (25-OHD3), and total cholesterol were significantly increased in young goats. Because this was not accompanied by any decrease in expression of CYP24A1 mRNA, we investigated mRNA expression of additional enzymes with known 24- and/or 25-hydroxylase activities (CYP2R1, CYP2J2, CYP3 A24, CYP27A1), receptors involved in their regulation (VDR, PXR, RXRα) and vitamin D binding protein (VDBP). CYP2R1expression was stimulated with the low dietary protein intake, negatively correlated with plasma urea and positively associated with serum 25-OHD3. The greater plasma concentrations of total cholesterol could be explained with the reduction of CYP2J2 and CYP27A1 expression. None of the receptors investigated were affected by the dietary protein restriction but mRNA expression of VDBP was slightly reduced. Taken together our results show that dietary protein restriction has an impact on vitamin D and cholesterol metabolism in ruminants, too. Therefore, further investigations are needed before dietary interventions aiming at diminishing nitrogen excretion can be implemented.
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Affiliation(s)
- Mirja R Wilkens
- Department of Physiology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15/102, 30173 Hannover, Germany
| | - Caroline S Firmenich
- Department of Physiology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15/102, 30173 Hannover, Germany
| | - Nadine Schnepel
- Department of Physiology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15/102, 30173 Hannover, Germany
| | - Alexandra S Muscher-Banse
- Department of Physiology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15/102, 30173 Hannover, Germany.
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9
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Mata-Greenwood E, Huber HF, Li C, Nathanielsz PW. Role of pregnancy and obesity on vitamin D status, transport, and metabolism in baboons. Am J Physiol Endocrinol Metab 2019; 316:E63-E72. [PMID: 30398904 PMCID: PMC6417685 DOI: 10.1152/ajpendo.00208.2018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 09/25/2018] [Accepted: 10/12/2018] [Indexed: 12/17/2022]
Abstract
Human studies show that obesity is associated with vitamin D insufficiency, which contributes to obesity-related disorders. Our aim was to elucidate the regulation of vitamin D during pregnancy and obesity in a nonhuman primate species. We studied lean and obese nonpregnant and pregnant baboons. Plasma 25-hydroxy vitamin D (25-OH-D) and 1α,25-(OH)2-D metabolites were analyzed using ELISA. Vitamin D-related gene expression was studied in maternal kidney, liver, subcutaneous fat, and placental tissue using real-time PCR and immunoblotting. Pregnancy was associated with an increase in plasma bioactive vitamin D levels compared with nonpregnant baboons in both lean and obese groups. Pregnant baboons had lower renal 24-hydroxylase CYP24A1 protein and chromatin-bound vitamin D receptor (VDR) than nonpregnant baboons. In contrast, pregnancy upregulated the expression of CYP24A1 and VDR in subcutaneous adipose tissue. Obesity decreased vitamin D status in pregnant baboons (162 ± 17 vs. 235 ± 28 nM for 25-OH-D, 671 ± 12 vs. 710 ± 10 pM for 1α,25-(OH)2-D; obese vs. lean pregnant baboons, P < 0.05). Lower vitamin D status correlated with decreased maternal renal expression of the vitamin D transporter cubulin and the 1α-hydroxylase CYP27B1. Maternal obesity also induced placental downregulation of the transporter megalin (LRP2), CYP27B1, the 25-hydroxylase CYP2J2, and VDR. We conclude that baboons represent a novel species to evaluate vitamin D regulation. Both pregnancy and obesity altered vitamin D status. Obesity-induced downregulation of vitamin D transport and bioactivation genes are novel mechanisms of obesity-induced vitamin D regulation.
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Affiliation(s)
- Eugenia Mata-Greenwood
- Lawrence Longo Center for Perinatal Biology, School of Medicine, Loma Linda University , Loma Linda, California
| | - Hillary F Huber
- Department of Animal Science, University of Wyoming , Laramie Wyoming
| | - Cun Li
- Department of Animal Science, University of Wyoming , Laramie Wyoming
- Southwest National Primate Research Center, Texas Biomedical Research Institute , San Antonio, Texas
| | - Peter W Nathanielsz
- Department of Animal Science, University of Wyoming , Laramie Wyoming
- Southwest National Primate Research Center, Texas Biomedical Research Institute , San Antonio, Texas
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