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Martinand-Mari C, Debiais-Thibaud M, Potier E, Gasset E, Dutto G, Leurs N, Lallement S, Farcy E. Estradiol-17β and bisphenol A affect growth and mineralization in early life stages of seabass. Comp Biochem Physiol C Toxicol Pharmacol 2024; 281:109921. [PMID: 38609061 DOI: 10.1016/j.cbpc.2024.109921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 03/22/2024] [Accepted: 04/07/2024] [Indexed: 04/14/2024]
Abstract
Natural and synthetic estrogens are contaminants present in aquatic ecosystems. They can have significant consequences on the estrogen-sensitive functions of organisms, including skeletal development and growth of vertebrate larvae. Synthetic polyphenols represent a group of environmental xenoestrogens capable of binding the receptors for the natural hormone estradiol-17β (E2). To better understand how (xeno-)estrogens can affect the skeleton in fish species with high ecological and commercial interest, 16 days post-hatch larvae of the seabass were experimentally exposed for 7 days to E2 and Bisphenol A (BPA), both used at the regulatory concentration of surface water quality (E2: 0.4 ng.L-1, BPA: 1.6 μg.L-1) or at a concentration 100 times higher. Skeletal mineralization levels were evaluated using Alizarin red staining, and expression of several genes playing key roles in growth, skeletogenesis and estrogen signaling pathways was assessed by qPCR. Our results show that E2 exerts an overall negative effect on skeletal mineralization at the environmental concentration of 0.4 ng.L-1, correlated with an increase in the expression of genes associated only with osteoblast bone cells. Both BPA exposures inhibited mineralization with less severe effects and modified bone homeostasis by regulating the expression of gene encoding osteoblasts and osteoclasts markers. Our results demonstrate that environmental E2 exposure inhibits larval growth and has an additional inhibitory effect on skeleton mineralization while both BPA exposures have marginal inhibitory effect on skeletal mineralization. All exposures have significant effects on transcriptional levels of genes involved in the skeletal development of seabass larvae.
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Affiliation(s)
- Camille Martinand-Mari
- Institut des Sciences de l'Evolution de Montpellier, ISEM, Univ. Montpellier, CNRS, IRD, France.
| | - Melanie Debiais-Thibaud
- Institut des Sciences de l'Evolution de Montpellier, ISEM, Univ. Montpellier, CNRS, IRD, France
| | - Eric Potier
- Marine Biodiversity, Exploitation and Conservation, MARBEC, Univ. Montpellier, Ifremer, CNRS, IRD, France
| | - Eric Gasset
- Marine Biodiversity, Exploitation and Conservation, MARBEC, Univ. Montpellier, Ifremer, CNRS, IRD, France
| | - Gilbert Dutto
- Marine Biodiversity, Exploitation and Conservation, MARBEC, Univ. Montpellier, Ifremer, CNRS, IRD, France
| | - Nicolas Leurs
- Institut des Sciences de l'Evolution de Montpellier, ISEM, Univ. Montpellier, CNRS, IRD, France
| | - Stéphane Lallement
- Marine Biodiversity, Exploitation and Conservation, MARBEC, Univ. Montpellier, Ifremer, CNRS, IRD, France
| | - Emilie Farcy
- Marine Biodiversity, Exploitation and Conservation, MARBEC, Univ. Montpellier, Ifremer, CNRS, IRD, France.
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Carreras-Badosa G, Puerto-Carranza E, Mas-Parés B, Gómez-Vilarrubla A, Cebrià-Fondevila H, Díaz-Roldán F, Riera-Pérez E, de Zegher F, Ibañez L, Bassols J, López-Bermejo A. Circulating free T3 associates longitudinally with cardio-metabolic risk factors in euthyroid children with higher TSH. Front Endocrinol (Lausanne) 2023; 14:1172720. [PMID: 37265695 PMCID: PMC10230068 DOI: 10.3389/fendo.2023.1172720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 05/03/2023] [Indexed: 06/03/2023] Open
Abstract
Introduction Thyroid hormones play major roles in the regulation of body composition and metabolism, and therefore, the relationship between thyroid hormones and cardio-metabolic risk has been extensively studied in adults. In this study, we aimed to test whether free triiodothyronine (fT3) associates longitudinally with cardio-metabolic risk factors in euthyroid children. Methods A prospective study cohort of 599 apparently healthy school-age children were assessed at baseline (mean age 8.1 ± 2.1 years), of whom 270 children were also assessed at follow-up (4 years later). Circulating thyroid-stimulating hormone (TSH), free thyroxine (fT4), and fT3 were measured, and cardio-metabolic risk was assessed by means of body mass index (BMI), waist circumference, visceral fat (by ultrasound), blood pressure, circulating lipids, and homeostasis model assessment of insulin resistance (HOMA-IR) index, both at baseline and at follow-up. Results All studied children had normal thyroid function tests. Independent associations between baseline fT3 and both baseline and follow-up BMI, systolic blood pressure, mean arterial blood pressure, triglycerides, and HOMA-IR were found using multivariate regression analysis (adjusting for sex and baseline age and BMI). Analyses of effect sizes showed that for each 1 unit-increase in baseline fT3 (pg/ml), follow-up BMI-standard deviation score (SDS) increased by 0.31 units (z-score) and systolic blood pressure by 6.6 units (mmHg). The observed longitudinal associations were more robust in children belonging to the upper TSH tertile who showed higher TSH levels and were characterized by weighing more and having the highest fT3 levels. In these children, for each 1 unit-increase in baseline fT3 (pg/ml), follow-up BMI-SDS increased by 0.67 units (z-score) and systolic blood pressure by 10.2 units (mmHg). Conclusions Circulating fT3 associates longitudinally with cardio-metabolic risk factors in euthyroid children with higher TSH. The observed associations of thyroid hormones in these children could conceivably respond to a homeostatic attempt to reduce their cardio-metabolic risk.
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Affiliation(s)
| | - Elsa Puerto-Carranza
- Pediatric Endocrinology Group, Girona Biomedical Research Institute, Girona, Spain
- Pediatrics, Dr. Josep Trueta Hospital, Girona, Spain
| | - Berta Mas-Parés
- Pediatric Endocrinology Group, Girona Biomedical Research Institute, Girona, Spain
| | | | | | - Ferran Díaz-Roldán
- Pediatric Endocrinology Group, Girona Biomedical Research Institute, Girona, Spain
| | | | - Francis de Zegher
- Department of Development and Regeneration, University of Leuven, Leuven, Belgium
| | - Lourdes Ibañez
- Sant Joan de Déu Children’s Hospital Pediatric Research Institute, University of Barcelona, Barcelona, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas, Instituto de Salud Carlos III, Madrid, Spain
| | - Judit Bassols
- Maternal-Fetal Metabolic Group, Girona Biomedical Research Institute, Girona, Spain
| | - Abel López-Bermejo
- Pediatric Endocrinology Group, Girona Biomedical Research Institute, Girona, Spain
- Pediatrics, Dr. Josep Trueta Hospital, Girona, Spain
- Department of Medical Sciences, University of Girona, Girona, Spain
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Zhang Y, Ahmadpoor X, Lin H. Roles of Local Soluble Factors in Maintaining the Growth Plate: An Update. Genes (Basel) 2023; 14:534. [PMID: 36980807 PMCID: PMC10048135 DOI: 10.3390/genes14030534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/16/2023] [Accepted: 02/18/2023] [Indexed: 02/24/2023] Open
Abstract
The growth plate is a cartilaginous tissue found at the ends of growing long bones, which contributes to the lengthening of bones during development. This unique structure contains at least three distinctive layers, including resting, proliferative, and hypertrophic chondrocyte zones, maintained by a complex regulatory network. Due to its soft tissue nature, the growth plate is the most susceptible tissue of the growing skeleton to injury in childhood. Although most growth plate damage in fractures can heal, some damage can result in growth arrest or disorder, impairing leg length and resulting in deformity. In this review, we re-visit previously established knowledge about the regulatory network that maintains the growth plate and integrate current research displaying the most recent progress. Next, we highlight local secretary factors, such as Wnt, Indian hedgehog (Ihh), and parathyroid hormone-related peptide (PTHrP), and dissect their roles and interactions in maintaining cell function and phenotype in different zones. Lastly, we discuss future research topics that can further our understanding of this unique tissue. Given the unmet need to engineer the growth plate, we also discuss the potential of creating particular patterns of soluble factors and generating them in vitro.
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Durham EL, Grey ZJ, Black L, Howie RN, Barth JL, Lee BS, Cray JJ. Sfrp4 expression in thyroxine treated calvarial cells. Life Sci 2022; 311:121158. [PMID: 36370870 PMCID: PMC9719041 DOI: 10.1016/j.lfs.2022.121158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/24/2022] [Accepted: 11/04/2022] [Indexed: 11/11/2022]
Abstract
AIMS Evidence suggests alterations of thyroid hormone levels can disrupt normal bone development. Most data suggest the major targets of thyroid hormones to be the Htra1/Igf1 pathway. Recent discovery by our group suggests involvement of targets WNT pathway, specifically overexpression of antagonist Sfrp4 in the presence of exogenous thyroid hormone. MAIN METHODS Here we aimed to model these interactions in vitro using primary and isotype cell lines to determine if thyroid hormone drives increased Sfrp4 expression in cells relevant to craniofacial development. Transcriptional profiling, bioinformatics interrogation, protein and function analyses were used. KEY FINDINGS Affymetrix transcriptional profiling found Sfrp4 overexpression in primary cranial suture derived cells stimulated with thyroxine in vitro. Interrogation of the SFRP4 promoter identified multiple putative binding sites for thyroid hormone receptors. Experimentation with several cell lines demonstrated that thyroxine treatment induced Sfrp4 expression, demonstrating that Sfrp4 mRNA and protein levels are not tightly coupled. Transcriptional and protein analyses demonstrate thyroid hormone receptor binding to the proximal promoter of the target gene Sfrp4 in murine calvarial pre-osteoblasts. Functional analysis after thyroxine hormone stimulation for alkaline phosphatase activity shows that pre-osteoblasts increase alkaline phosphatase activity compared to other cell types, suggesting cell type susceptibility. Finally, we added recombinant SFRP4 to pre-osteoblasts in combination with thyroxine treatment and observed a significant decrease in alkaline phosphatase positivity. SIGNIFICANCE Taken together, these results suggest SFRP4 may be a key regulatory molecule that prevents thyroxine driven osteogenesis. These data corroborate clinical findings indicating a potential for SFRP4 as a diagnostic or therapeutic target for hyperostotic craniofacial disorders.
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Affiliation(s)
- Emily L Durham
- Department of Oral Health Sciences, Medical University of South Carolina, Charleston, SC, USA; Department of Pediatrics, Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Zachary J Grey
- Department of Oral Health Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Laurel Black
- Department of Oral Health Sciences, Medical University of South Carolina, Charleston, SC, USA; Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - R Nicole Howie
- Department of Oral Health Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Jeremy L Barth
- Department of Regenerative Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Beth S Lee
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - James J Cray
- Department of Biomedical Education and Anatomy, College of Medicine, The Ohio State University, Columbus, OH, USA; Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA.
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Inzaghi E, Pampanini V, Deodati A, Cianfarani S. The Effects of Nutrition on Linear Growth. Nutrients 2022; 14:1752. [PMID: 35565716 DOI: 10.3390/nu14091752] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 04/10/2022] [Accepted: 04/17/2022] [Indexed: 12/16/2022] Open
Abstract
Linear growth is a complex process and is considered one of the best indicators of children’s well-being and health. Genetics, epigenetics and environment (mainly stress and availability of nutrients) are the main regulators of growth. Nutrition exerts its effects on growth throughout the course of life with different, not completely understood mechanisms. Cells have a sophisticated sensing system, which allows growth processes to occur in the presence of an adequate nutrient availability. Most of the nutritional influence on growth is mediated by hormonal signals, in turn sensitive to nutritional cues. Both macro- and micro-nutrients are required for normal growth, as demonstrated by the impairment of growth occurring when their intake is insufficient. Clinical conditions characterized by abnormal nutritional status, including obesity and eating disorders, are associated with alterations of growth pattern, confirming the tight link between growth and nutrition. The precise molecular mechanisms connecting nutrition to linear growth are far from being fully understood and further studies are required. A better understanding of the interplay between nutrients and the endocrine system will allow one to develop more appropriate and effective nutritional interventions for optimizing child growth.
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Mengeling BJ, Vetter LF, Furlow JD. Retinoid-X receptor agonists increase thyroid hormone competence in lower jaw remodeling of pre-metamorphic Xenopus laevis tadpoles. PLoS One 2022; 17:e0266946. [PMID: 35417489 PMCID: PMC9007347 DOI: 10.1371/journal.pone.0266946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 03/30/2022] [Indexed: 11/18/2022] Open
Abstract
Thyroid hormone (TH) signaling plays critical roles during vertebrate development, including regulation of skeletal and cartilage growth. TH acts through its receptors (TRs), nuclear hormone receptors (NRs) that heterodimerize with Retinoid-X receptors (RXRs), to regulate gene expression. A defining difference between NR signaling during development compared to in adult tissues, is competence, the ability of the organism to respond to an endocrine signal. Amphibian metamorphosis, especially in Xenopus laevis, the African clawed frog, is a well-established in vivo model for studying the mechanisms of TH action during development. Previously, we’ve used one-week post-fertilization X. laevis tadpoles, which are only partially competent to TH, to show that in the tail, which is naturally refractive to exogenous T3 at this stage, RXR agonists increase TH competence, and that RXR antagonism inhibits the TH response. Here, we focused on the jaw that undergoes dramatic TH-mediated remodeling during metamorphosis in order to support new feeding and breathing styles. We used a battery of approaches in one-week-old tadpoles, including quantitative morphology, differential gene expression and whole mount cell proliferation assays, to show that both pharmacologic (bexarotene) and environmental (tributyltin) RXR agonists potentiated TH-induced responses but were inactive in the absence of TH; and the RXR antagonist UVI 3003 inhibited TH action. Bex and TBT significantly potentiated cellular proliferation and the TH induction of runx2, a transcription factor critical for developing cartilage and bone. Prominent targets of RXR-mediated TH potentiation were members of the matrix metalloprotease family, suggesting that RXR potentiation may emphasize pathways responsible for rapid changes during development.
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Affiliation(s)
- Brenda J. Mengeling
- Department of Neurobiology, Physiology, and Behavior, College of Biological Sciences, University of California, Davis, California, United States of America
- * E-mail:
| | - Lara F. Vetter
- Department of Neurobiology, Physiology, and Behavior, College of Biological Sciences, University of California, Davis, California, United States of America
| | - J. David Furlow
- Department of Neurobiology, Physiology, and Behavior, College of Biological Sciences, University of California, Davis, California, United States of America
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Araújo FR, Bertassoli BM, Ocarino NM, Reis AMS, Silva JF, Ribeiro LGR, Serakides R. Maternal Hyperthyroidism in Rats Alters the Composition and Gene Expression of the Matrix Produced In Vitro by Chondrocytes from Offspring with Intrauterine Growth Restriction. Metabolites 2022; 12:292. [PMID: 35448479 PMCID: PMC9027694 DOI: 10.3390/metabo12040292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/23/2022] [Accepted: 03/24/2022] [Indexed: 11/26/2022] Open
Abstract
Herein, we aimed to evaluate cultures of femoral chondrocytes from offspring of rats with intrauterine growth restriction (IUGR) induced by maternal hyperthyroidism. Fourteen adult female Wistar rats were divided into two groups, a control group and a group treated with daily L-thyroxine administration using an orogastric tube (50 µg/animal/day) during pregnancy. Three days after birth, the offspring were euthanized for chondrocyte extraction. At 7, 14, and 21 days, viability and alkaline-phosphatase (ALP) activity were assessed using the MTT assay and BCIP/NBT method, respectively, in a 2D culture. Pellets (3D cultures) were stained with periodic acid Schiff (PAS) to assess the morphology and percentage of PAS+ areas. The gene transcripts for Col2, Col10, Acan, Sox9, and Runx2 were evaluated by qRT-PCR. The MTT and ALP-assay results showed no significant differences between the groups. Maternal hyperthyroidism did not alter the chondrocyte morphology, but significantly reduced the percentage of PAS+ areas, decreased the expression of the gene transcripts of Col2 and Acan, and increased Sox9 expression. Maternal hyperthyroidism in rats alters the composition and gene expression of the matrix produced by chondrocytes from offspring with IUGR. This may be one of the mechanisms through which excess maternal thyroid hormones reduce offspring bone growth.
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Zhang R, Yan K, Wu Y, Yao X, Li G, Ge L, Chen Z. Quantitative proteomics reveals the effect of Yigu decoction (YGD) on protein expression in bone tissue. Clin Proteomics 2021; 18:24. [PMID: 34641785 PMCID: PMC8513338 DOI: 10.1186/s12014-021-09330-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 09/29/2021] [Indexed: 08/30/2023] Open
Abstract
Background Osteoporosis (OP) is a systemic bone disease characterized by decreased bone mass, destruction of the bone tissue microstructure, increased bone brittleness and an increased risk of fracture. OP has a high incidence rate and long disease course and is associated with serious complications. Yigu decoction (YGD) is a compound prescription in traditional Chinese medicine that is used to treat OP. However, its mechanism in OP is not clear. This study used a tandem mass tag (TMT)quantitative proteomics method to explore the potential bone-protective mechanism of YGD in an osteoporotic rat model. Materials and methods A rat model of OP was established by ovariectomy. Eighteen 12-week-old specific-pathogen-free female Wistar rats weighing 220 ± 10 g were selected. The eighteen rats were randomly divided into 3 groups (n = 6 in each group): the normal, model and YGD groups. The right femurs from each group were subjected to quantitative biological analysis. TMT quantitative proteomics was used to analyze the proteins extracted from the bone tissue of rats in the model and YGD groups, and the differentially expressed proteins after intervention with YGD were identified as biologically relevant proteins of interest. Functional annotation correlation analysis was also performed to explore the biological function and mechanism of YGD. Result Compared with the model group, the YGD group showed significant upregulation of 26 proteins (FC > 1.2, P < 0.05) and significant downregulation of 39 proteins (FC < 0.833, P < 0.05). Four important targets involved in OP and 5 important signaling pathways involved in bone metabolism were identified. Conclusions YGD can significantly increase the bone mineral density (BMD) of osteoporotic rats and may play a therapeutic role by regulating target proteins involved in multiple signaling pathways. Therefore, these results improve the understanding of the OP mechanism and provide an experimental basis for the clinical application of YGD in OP treatment. Supplementary Information The online version contains supplementary material available at 10.1186/s12014-021-09330-0.
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Affiliation(s)
- Ruikun Zhang
- The Third Clinical Medical College of Zhejiang, Chinese Medical University, Zhejiang, Hangzhou, 310053, China.,Department of Orthopedics, The Third Affiliated Hospital of Zhejiang, Chinese Medical University, Zhejiang, Hangzhou, 310005, China
| | - Kun Yan
- The Third Clinical Medical College of Zhejiang, Chinese Medical University, Zhejiang, Hangzhou, 310053, China.,Department of Orthopedics, The Third Affiliated Hospital of Zhejiang, Chinese Medical University, Zhejiang, Hangzhou, 310005, China
| | - Yulun Wu
- Rehabilitation Medicine Center of Zhejiang Provincial People's Hospital, Rehabilitation & Sports Medicine Research Institute of Zhejiang Province, People's Hospital of Hangzhou Medical College, Hangzhou, 310014, China
| | - Xinmiao Yao
- The Third Clinical Medical College of Zhejiang, Chinese Medical University, Zhejiang, Hangzhou, 310053, China.,Department of Orthopedics, The Third Affiliated Hospital of Zhejiang, Chinese Medical University, Zhejiang, Hangzhou, 310005, China
| | - Guijin Li
- Department of Orthopedics, The Third Affiliated Hospital of Zhejiang, Chinese Medical University, Zhejiang, Hangzhou, 310005, China
| | - Linpu Ge
- Department of Orthopedics, The Third Affiliated Hospital of Zhejiang, Chinese Medical University, Zhejiang, Hangzhou, 310005, China
| | - Zhineng Chen
- Department of Orthopedics, The Third Affiliated Hospital of Zhejiang, Chinese Medical University, Zhejiang, Hangzhou, 310005, China.
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Wang W, Yang Y, Chen A, Song X, Chai L. Inhibition of Metamorphosis, Thyroid Gland, and Skeletal Ossification Induced by Hexavalent Chromium in Bufo gargarizans Larvae. Environ Toxicol Chem 2021; 40:2474-2483. [PMID: 34003524 DOI: 10.1002/etc.5114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 01/19/2021] [Accepted: 05/07/2021] [Indexed: 06/12/2023]
Abstract
Hexavalent chromium (Cr [VI]) is one of the major detrimental heavy metal pollutants. In the present study, Bufo gargarizans were exposed to 0, 52, 104, 208, and 416 μg/L Cr (VI) from Gosner stage 2 until metamorphosis; and growth, development, and histological characteristics of the thyroid gland and skeletal ossification were examined. The results demonstrated that the survival rate of larvae exposed to Cr (VI) was not different from that measured in animals from the control group. However, high levels of Cr (VI) (104, 208, and 416 μg/L) were associated with significantly delayed growth and development. The suppression of skeletal ossification was observed at high Cr (VI) levels. Besides, histological alterations of the thyroid gland, such as follicular cell hyperplasia, colloid depletion, and peripheral colloid vacuolation, were found in 52 to 416 μg/L Cr (VI) treatments. The results of the present study highlight reductions in growth and development as well as percent metamorphosis and skeletal ossification due to histological alteration of the thyroid gland during exposure to Cr (VI) in B. gargarizans larvae. The present investigation could provide a basis for understanding the detrimental effects of Cr (VI) in amphibian larvae. Environ Toxicol Chem 2021;40:2474-2483. © 2021 SETAC.
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Affiliation(s)
- Wenxiang Wang
- School of Water and Environment, Chang'an University, Xi'an, China
- Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an, China
| | - Yijie Yang
- School of Water and Environment, Chang'an University, Xi'an, China
- Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an, China
| | - Aixia Chen
- School of Water and Environment, Chang'an University, Xi'an, China
- Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an, China
| | - Xiuling Song
- School of Water and Environment, Chang'an University, Xi'an, China
- Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an, China
| | - Lihong Chai
- School of Water and Environment, Chang'an University, Xi'an, China
- Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an, China
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Bennett KA, Robinson KJ, Armstrong HC, Moss SEW, Scholl G, Tranganida A, Eppe G, Thomé JP, Debier C, Hall AJ. Predicting consequences of POP-induced disruption of blubber glucose uptake, mass gain rate and thyroid hormone levels for weaning mass in grey seal pups. Environ Int 2021; 152:106506. [PMID: 33770584 DOI: 10.1016/j.envint.2021.106506] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 03/01/2021] [Accepted: 03/04/2021] [Indexed: 06/12/2023]
Abstract
Persistent organic pollutants (POPs) are endocrine disruptors that alter adipose tissue development, regulation and function. Top marine predators are particularly vulnerable because they possess large fat stores that accumulate POPs. However, links between endocrine or adipose tissue function disruption and whole animal energetics have rarely been investigated. We predicted the impact of alterations to blubber metabolic characteristics and circulating thyroid hormone (TH) levels associated with polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs) on suckling mass gain and weaning mass in wild grey seal pups. Glucose uptake by inner blubber was a strong predictor of whole animal mass gain rate, which in turn, resulted in heavier weaning mass. Weaning mass was predicted to increase by 3.7 ± 1.59 (sem) %, through increased mass gain rate, in the absence of the previously reported suppressive effect of dioxin-like PCB (DL-PCBs) on blubber glucose uptake. PBDEs were, conversely, associated with faster mass gain. Alleviation of this effect was predicted to reduce weaning mass by 6.02 ± 1.86% (sem). To better predict POPs effects on energy balance, it is crucial to determine if and how PBDEs promote mass gain in grey seal pups. Weaning mass was negatively related to total T3 (TT3) levels. A 20% (range = 9.3-31.7%) reduction in TT3 by DL-PCBs partially overcame the effect of DL-PCB -mediated reduction in blubber glucose uptake. Overall, DL-PCBs were thus predicted to reduce weaning mass by 1.86 ± 1.60%. Organohalogen impacts on whole-animal energy balance in grey seal pups appear to partially offset each other through opposing effects on different mechanisms. POP effects were generally minor, but the largest POP-induced reductions in weaning mass were predicted to occur in pups that were already small. Since weaning mass is positively related to first-year survival, POPs may disproportionately affect smaller individuals, and could continue to have population-level impacts even when levels are relatively low compared to historical values. Our findings show how in vitro experiments combined with measurements in vivo can help elucidate mechanisms that underpin energy balance regulation and help to quantify the magnitude of disruptive effects by contaminants and other stressors in wildlife.
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Affiliation(s)
- Kimberley A Bennett
- Division of Health Sciences, School of Applied Sciences, Abertay University, Kydd Building, Bell St., Dundee DD1 1HG, UK.
| | - Kelly J Robinson
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY 16 8LB, UK; Centre for Biological Diversity, Sir Harold Mitchell Building, University of St Andrews, Greenside Place, St Andrews, Fife KY16 9TF, UK.
| | - Holly C Armstrong
- Division of Health Sciences, School of Applied Sciences, Abertay University, Kydd Building, Bell St., Dundee DD1 1HG, UK.
| | - Simon E W Moss
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY 16 8LB, UK.
| | - Georges Scholl
- Center for Analytical Research and Technology (CART), Research Unit MolSys, B6c, Department of Chemistry, Université de Liège, 4000 Liege, Belgium.
| | - Alexandra Tranganida
- Division of Health Sciences, School of Applied Sciences, Abertay University, Kydd Building, Bell St., Dundee DD1 1HG, UK.
| | - Gauthier Eppe
- Center for Analytical Research and Technology (CART), Research Unit MolSys, B6c, Department of Chemistry, Université de Liège, 4000 Liege, Belgium.
| | - Jean-Pierre Thomé
- Center for Analytical Research and Technology (CART), Laboratory of Animal Ecology and Ecotoxicology (LEAE), Université de Liège, 4000 Liege, Belgium.
| | - Cathy Debier
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium.
| | - Ailsa J Hall
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife KY 16 8LB, UK.
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11
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Zekri Y, Flamant F, Gauthier K. Central vs. Peripheral Action of Thyroid Hormone in Adaptive Thermogenesis: A Burning Topic. Cells 2021; 10:1327. [PMID: 34071979 DOI: 10.3390/cells10061327] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/18/2021] [Accepted: 05/25/2021] [Indexed: 12/12/2022] Open
Abstract
Thyroid hormones (TH) contribute to the control of adaptive thermogenesis, which is associated with both higher energy expenditure and lower body mass index. While it was clearly established that TH act directly in the target tissues to fulfill its metabolic activities, some studies have rather suggested that TH act in the hypothalamus to control these processes. This paradigm shift has subjected the topic to intense debates. This review aims to recapitulate how TH control adaptive thermogenesis and to what extent the brain is involved in this process. This is of crucial importance for the design of new pharmacological agents that would take advantage of the TH metabolic properties.
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12
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Crank MN, Cottrell JN, Mitchell BL, Valentovic MA. Characterization of Fetal Thyroid Levels at Delivery among Appalachian Infants. J Clin Med 2020; 9:E3056. [PMID: 32971885 DOI: 10.3390/jcm9093056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 09/10/2020] [Accepted: 09/17/2020] [Indexed: 11/22/2022] Open
Abstract
Thyroid disorders are a frequently encountered issue during pregnancy and a cause of maternal and fetal morbidity. In regions like Appalachia that are particularly susceptible to health disparities, descriptive studies are needed to assist in identifying pathologic derangements. We sought to characterize fetal thyroid hormone levels at delivery and investigate whether or not maternal demographic characteristics affect the prevalence of neonatal thyroid disease. A cross-sectional analysis was conducted on 130 pregnant women recruited from the Tri-State region, incorporating areas of Kentucky, Ohio, and West Virginia. Total triiodothyronine (T3) (p = 0.4799), free T3 (p = 0.6323), T3 uptake (p = 0.0926), total thyroxine (T4) (p = 0.8316), free T4 (p = 0.0566), and Thyroid stimulating hormone (TSH) (p = 0.8745) levels were comparable between urban and rural newborns. We found no effect of hypertension status or nicotine levels on fetal umbilical cord thyroid hormone levels. Maternal diabetic status was associated with lower T4 (p = 0.0099) and free T4 (p = 0.0025) levels. Cotinine affected levels of T4 (p = 0.0339). In regard to maternal Body Mass Index (BMI), there was an increase in total T3 as BMI increased (p = 0.0367) and no significant difference in free T3, T3 uptake, T4, free T4, or TSH. There was a negative correlation between TSH and 1 min Apgar scores (p = 0.0058). Lead and cadmium have been implicated to alter TSH levels, but no correlation was found in our study (r2 = 0.0277). There were no differences in cord blood between urban (37.3 ± 10.3 fmol/ug DNA) and rural (70.5 ± 26.8 fmol/ug DNA) benzo(a)pyrene DNA adducts (p = 0.174). Thyroid disorders present a unique opportunity for the prevention of perinatal morbidity and mortality, since maternal treatment, as well as maternal demographic characteristics, can have direct fetal effects.
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13
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Abstract
The development of the craniofacial skeleton relies on complex temporospatial organization of diverse cell types by key signalling molecules. Even minor disruptions to these processes can result in deleterious consequences for the structure and function of the skull. Thyroid hormone deficiency causes delayed craniofacial and tooth development, dysplastic facial features and delayed development of the ossicles in the middle ear. Thyroid hormone excess, by contrast, accelerates development of the skull and, in severe cases, might lead to craniosynostosis with neurological sequelae and facial hypoplasia. The pathogenesis of these important abnormalities remains poorly understood and underinvestigated. The orchestration of craniofacial development and regulation of suture and synchondrosis growth is dependent on several critical signalling pathways. The underlying mechanisms by which these key pathways regulate craniofacial growth and maturation are largely unclear, but studies of single-gene disorders resulting in craniofacial malformations have identified a number of critical signalling molecules and receptors. The craniofacial consequences resulting from gain-of-function and loss-of-function mutations affecting insulin-like growth factor 1, fibroblast growth factor receptor and WNT signalling are similar to the effects of altered thyroid status and mutations affecting thyroid hormone action, suggesting that these critical pathways interact in the regulation of craniofacial development.
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Affiliation(s)
- Victoria D Leitch
- Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
- Royal Melbourne Institute of Technology (RMIT) Centre for Additive Manufacturing, RMIT University, Melbourne, VIC, Australia
| | - J H Duncan Bassett
- Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
| | - Graham R Williams
- Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
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14
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Ma Y, Ladisa C, Chang JP, Habibi HR. Multifactorial control of reproductive and growth axis in male goldfish: Influences of GnRH, GnIH and thyroid hormone. Mol Cell Endocrinol 2020; 500:110629. [PMID: 31678419 DOI: 10.1016/j.mce.2019.110629] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 10/17/2019] [Accepted: 10/18/2019] [Indexed: 01/24/2023]
Abstract
Reproduction and growth are under multifactorial control of neurohormones and peripheral hormones. This study investigated seasonally related effects of GnIH, GnRH, and T3 on the reproductive and growth axis in male goldfish at three stages of gonadal recrudescence. The effects of injection treatments with GnRH, GnIH and/or T3 were examined by measuring serum LH and GH levels, as well as peripheral transcript levels, using a factorial design. As expected, GnRH elevated serum LH and GH levels in a seasonally dependant manner, with maximal elevations of LH in late stages of gonadal recrudescence (Spring) and maximal increases in GH in the regressed gonadal stage (Summer). GnIH injection increased serum LH and GH levels only in fish at the regressed stage but exerted both stimulatory and inhibitory effects on GnRH-induced LH responses depending on season. T3 treatment mainly had stimulatory effects on circulating LH levels and inhibitory effects on serum GH concentrations. In the liver and testes, we observed seasonal differences in thyroid receptors, estrogen receptors, vitellogenin, follicle-stimulating hormone receptor, aromatase and IGF-I transcript levels that were tissue- and sex-specific. Generally, there were no clear correlation between circulating LH and GH levels and peripheral transcript levels, presumably due to time-related response and possible direct interaction of GnRH and GnIH at the level of liver and testis. The results support the hypothesis that GnRH and GnIH are important components of multifactorial mechanisms that work in concert with T3 to regulate reciprocal control of reproduction and growth in goldfish.
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Affiliation(s)
- Y Ma
- Department of Biological Sciences University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada, T2N 1N4
| | - C Ladisa
- Department of Biological Sciences University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada, T2N 1N4
| | - J P Chang
- Department of Biological Sciences University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada, T2N 1N4; Department of Biological Sciences University of Alberta, Edmonton, Alberta, Canada, T6G 2E9
| | - H R Habibi
- Department of Biological Sciences University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada, T2N 1N4.
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15
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Ma Y, Ladisa C, Chang JP, Habibi HR. Seasonal Related Multifactorial Control of Pituitary Gonadotropin and Growth Hormone in Female Goldfish: Influences of Neuropeptides and Thyroid Hormone. Front Endocrinol (Lausanne) 2020; 11:175. [PMID: 32318022 PMCID: PMC7154077 DOI: 10.3389/fendo.2020.00175] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 03/11/2020] [Indexed: 12/13/2022] Open
Abstract
Female reproduction is under multifactorial control of brain-pituitary-peripheral origin. The present study provides information on seasonal changes in circulating LH and GH concentrations, as well as transcript levels for a number of genes involved in the regulation of reproduction and growth in female goldfish. We also provide information on the effects of treatments with GnRH and/or GnIH, and their interaction with T3, at three stages of gonadal recrudescence. Maximum basal concentration of LH was observed at late recrudescence (Spring) while no seasonal changes in basal serum GH levels was detected. Serum LH and GH levels were stimulated by GnRH as expected, depending on the season. GnIH stimulated basal GH concentrations in gonadally regressed fish. GnIH inhibitory action on GnRH-induced LH response was observed in late, but not in mid recrudescence. T3 actions on basal and GnRH- or GnIH-induced GH secretion were generally inhibitory, depending on season. Administration of T3 attenuated GnRH-induced LH responses in mid and late stages of gonadal recrudescence, and the presence of GnIH abolished inhibitory actions of T3 in fish at mid recrudescence. Our results also demonstrated seasonal patterns in basal and GnRH- and/or GnIH-induced transcript levels for ERα, ERβI, FSHR, aromatase, TRαI, TRβ, IGF-I, and Vtg in the liver and ovary. However, there were no clear correlations between changes in transcript levels and circulating levels of LH and GH. The results support the hypothesis that GnRH, GnIH, and T3 are contributing factors in complex reciprocal control of reproduction and growth in goldfish.
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Affiliation(s)
- Yifei Ma
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Claudia Ladisa
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - John P. Chang
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Hamid R. Habibi
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
- *Correspondence: Hamid R. Habibi
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16
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Abstract
Thyroid hormone (TH) levels increase rapidly during the prepubertal growth period in mice, and this change is necessary for endochondral ossification of the epiphyses. This effect of TH on epiphyseal chondrocyte hypertrophy is mediated via TRβ1. In addition to its traditional genomic signaling role as a transcription factor, TRβ1 can also exert nongenomic effects by interacting with other signaling molecules such as PI3K. To investigate the role of nongenomic TRβ1 signaling in endochondral ossification, we evaluated the skeletal phenotype of TRβ147F mutant mice which exhibit a normal genomic response of TRβ1 to TH, but the nongenomic response through the PI3K pathway is impaired. Using microCT, we found that 13-week-old TRβ147F mice had significantly less trabecular bone mass at three sites. Histomorphometric analyses revealed that mineralizing surface to bone surface and BFR/BS were reduced in the mutant mice. Mechanistically, we found that activation of TRβ increased Alp and Osx expression in control but not TRβ147F osteoblasts. Since canonical β-catenin signaling has been implicated in mediating nongenomic TRβ-PI3K signaling, we evaluated the effect of TRβ1 activation on β-catenin target gene expression in MC3T3-E1 pre-osteoblasts. We found that β-catenin target genes were increased, suggesting that nongenomic TRβ1-PI3K pathway modulation of β-catenin signaling may mediate TRβ1 effects on osteoblast differentiation. Together, these results suggest that TH acting through TRβ1 regulates endochondral ossification in part via nongenomic signaling in mice. Further investigation of this nongenomic mechanism of TRβ1 signaling could lead to novel therapeutic targets for treatment and prevention of osteoporosis.
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Affiliation(s)
- Richard C. Lindsey
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA, USA
- Center for Health Disparities and Molecular Medicine, School of Medicine, Loma Linda University, Loma Linda, CA, USA
- Division of Biochemistry, Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Catrina Godwin
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA, USA
| | - Subburaman Mohan
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA, USA
- Center for Health Disparities and Molecular Medicine, School of Medicine, Loma Linda University, Loma Linda, CA, USA
- Division of Biochemistry, Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, USA
- Department of Medicine, School of Medicine, Loma Linda University, Loma Linda, CA, USA
- Department of Orthopedics, School of Medicine, Loma Linda University, Loma Linda, CA, USA
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Bianco AC, Dumitrescu A, Gereben B, Ribeiro MO, Fonseca TL, Fernandes GW, Bocco BMLC. Paradigms of Dynamic Control of Thyroid Hormone Signaling. Endocr Rev 2019; 40:1000-1047. [PMID: 31033998 PMCID: PMC6596318 DOI: 10.1210/er.2018-00275] [Citation(s) in RCA: 140] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 03/15/2019] [Indexed: 12/17/2022]
Abstract
Thyroid hormone (TH) molecules enter cells via membrane transporters and, depending on the cell type, can be activated (i.e., T4 to T3 conversion) or inactivated (i.e., T3 to 3,3'-diiodo-l-thyronine or T4 to reverse T3 conversion). These reactions are catalyzed by the deiodinases. The biologically active hormone, T3, eventually binds to intracellular TH receptors (TRs), TRα and TRβ, and initiate TH signaling, that is, regulation of target genes and other metabolic pathways. At least three families of transmembrane transporters, MCT, OATP, and LAT, facilitate the entry of TH into cells, which follow the gradient of free hormone between the extracellular fluid and the cytoplasm. Inactivation or marked downregulation of TH transporters can dampen TH signaling. At the same time, dynamic modifications in the expression or activity of TRs and transcriptional coregulators can affect positively or negatively the intensity of TH signaling. However, the deiodinases are the element that provides greatest amplitude in dynamic control of TH signaling. Cells that express the activating deiodinase DIO2 can rapidly enhance TH signaling due to intracellular buildup of T3. In contrast, TH signaling is dampened in cells that express the inactivating deiodinase DIO3. This explains how THs can regulate pathways in development, metabolism, and growth, despite rather stable levels in the circulation. As a consequence, TH signaling is unique for each cell (tissue or organ), depending on circulating TH levels and on the exclusive blend of transporters, deiodinases, and TRs present in each cell. In this review we explore the key mechanisms underlying customization of TH signaling during development, in health and in disease states.
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Affiliation(s)
- Antonio C Bianco
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
| | - Alexandra Dumitrescu
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
| | - Balázs Gereben
- Department of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Miriam O Ribeiro
- Developmental Disorders Program, Center of Biologic Sciences and Health, Mackenzie Presbyterian University, São Paulo, São Paulo, Brazil
| | - Tatiana L Fonseca
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
| | - Gustavo W Fernandes
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
| | - Barbara M L C Bocco
- Section of Endocrinology, Diabetes, and Metabolism, University of Chicago Medical Center, Chicago, Illinois
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18
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19
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Martins GM, Teixeira MBCG, Silva MV, Neofiti-Papi B, Miranda-Rodrigues M, Brum PC, Gouveia CHA. Global Disruption of α2A Adrenoceptor Barely Affects Bone Tissue but Minimizes the Detrimental Effects of Thyrotoxicosis on Cortical Bone. Front Endocrinol (Lausanne) 2018; 9:486. [PMID: 30233491 PMCID: PMC6127616 DOI: 10.3389/fendo.2018.00486] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 08/06/2018] [Indexed: 01/02/2023] Open
Abstract
Evidence shows that sympathetic nervous system (SNS) activation inhibits bone formation and activates bone resorption leading to bone loss. Because thyroid hormone (TH) interacts with the SNS to control several physiological processes, we raised the hypothesis that this interaction also controls bone remodeling. We have previously shown that mice with double-gene inactivation of α2A- and -adrenoceptors (α2A/2C-AR-/-) present high bone mass (HBM) phenotype and resistance to thyrotoxicosis-induced osteopenia, which supports a TH-SNS interaction to control bone mass and suggests that it involves α2-AR signaling. Accordingly, we detected expression of α2A-AR, α2B-AR and α2C-AR in the skeleton, and that triiodothyronine (T3) modulates α2C-AR mRNA expression in the bone. Later, we found that mice with single-gene inactivation of α2C-AR (α2C-AR-/-) present low bone mass in the femur and HBM in the vertebra, but that both skeletal sites are resistant to TH-induce osteopenia, showing that the SNS actions occur in a skeletal site-dependent manner, and that thyrotoxicosis depends on α2C-AR signaling to promote bone loss. To further dissect the specific roles of α2-AR subtypes, in this study, we evaluated the skeletal phenotype of mice with single-gene inactivation of α2A-AR (α2A-AR-/-), and the effect of daily treatment with a supraphysiological dose of T3, for 4 or 12 weeks, on bone microarchitecture and bone resistance to fracture. Micro-computed tomographic (μCT) analysis revealed normal trabecular and cortical bone structure in the femur and vertebra of euthyroid α2A-AR-/- mice. Thyrotoxicosis was more detrimental to femoral trabecular bone in α2A-AR-/- than in WT mice, whereas this bone compartment had been previously shown to present resistance to thyrotoxicosis in α2C-AR-/- mice. Altogether these findings reveal that TH excess depends on α2C-AR signaling to negatively affect femoral trabecular bone. In contrast, thyrotoxicosis was more deleterious to femoral and vertebral cortical bone in WT than in α2A-AR-/- mice, suggesting that α2A-AR signaling contributes to TH actions on cortical bone. These findings further support a TH-SNS interaction to control bone physiology, and suggest that α2A-AR and α2C-AR signaling pathways have key roles in the mechanisms through which thyrotoxicosis promotes its detrimental effects on bone remodeling, structure and resistance to fracture.
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Affiliation(s)
- Gisele M. Martins
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- Department of Morphology, Federal University of Espírito Santo, Vitória, Brazil
| | | | - Marcos V. Silva
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- Department of Morphology, Federal University of Sergipe, Aracaju, Brazil
| | - Bianca Neofiti-Papi
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- School of Medicine, University of São Paulo, São Paulo, Brazil
| | - Manuela Miranda-Rodrigues
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- University of Western Ontario, London, ON, Canada
| | - Patricia C. Brum
- School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Cecilia H. A. Gouveia
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- School of Medicine, University of São Paulo, São Paulo, Brazil
- *Correspondence: Cecilia H. A. Gouveia
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